%0 Journal Article
%~ PubMed
%A Dimou, S
%A Battisti, R A
%A Hermens, D F
%A Lagopoulos, J
%T A systematic review of functional magnetic resonance imaging and diffusion tensor imaging modalities used in presurgical planning of brain tumour resection.
%B Neurosurgical Review
%D 2013
%C Germany
%I Springer
%V 36
%N 2
%P 205-214
%@ 1437-2320
%X 
%Z FOR Codes: 110323


%0 Journal Article
%~ PubMed
%A Hickie, Ian B
%A Scott, Elizabeth M
%A Hermens, Daniel F
%A Naismith, Sharon L
%A Guastella, Adam J
%A Kaur, Manreena
%A Sidis, Anna
%A Whitwell, Bradley
%A Glozier, Nicholas
%A Davenport, Tracey
%A Pantelis, Christos
%A Wood, Stephen J
%A McGorry, Patrick D
%T Applying clinical staging to young people who present for mental health care.
%B Early Intervention in Psychiatry
%D 2013
%C Australia
%I Wiley-Blackwell Publishing Asia
%V 7
%N 1
%P 31-43
%@ 1751-7893
%X Aim: The study aims to apply clinical staging to young people who present for mental health care; to describe the demographic features, patterns of psychological symptoms, disability correlates and clinical stages of those young people; and to report longitudinal estimates of progression from less to more severe stages. Methods: The study uses cross-sectional and longitudinal assessments of young people managed in specialized youth clinics. On the basis of clinical records, subjects were assigned to a specific clinical ''stage'' (i.e. ''help-seeking'', ''attenuated syndrome'', ''discrete disorder'' or ''persistent or recurrent illness''). Results: Young people (n???=???209, mean age???=???19.9???years (range???=???12-30???years), 48% female) were selected from a broader cohort of n???=???1483 subjects. Ten percent were assigned to the earliest ''help-seeking'' stage, 54% to the ''attenuated syndrome'' stage, 25% to the ''discrete disorder'' stage and 11% to the later ''persistent or recurrent illness'' stage. The interrater reliability of independent ratings at baseline was acceptable (?????=???0.71). Subjects assigned to the ''attenuated syndrome'' stage reported symptom and disability scores that were similar to those assigned to later stages. Longitudinally (median???=???48???weeks), transition to later clinical stages were 11% of the ''help-seeking'', 19% of the ''attenuated syndrome'' and 33% of the ''discrete disorder'' groups. Conclusion: Among young people presenting for mental health care, most are clinically staged as having ''attenuated syndromes''. Despite access to specialized treatment, a significant number progress to more severe or persistent disorders.
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Lee, R S C
%A Redoblado-Hodge, M A
%A Naismith, S L
%A Hermens, D F
%A Porter, M A
%A Hickie, I B
%T Cognitive remediation improves memory and psychosocial functioning in first-episode psychiatric out-patients.
%B Psychological Medicine
%D 2013
%C United Kingdom
%I Cambridge University Press
%V 46
%N 6
%P 1161-1173
%@ 0033-2917
%X 
%Z FOR Codes: 110319 170101


%0 Journal Article
%~ PubMed
%A Robillard, R??becca
%A Naismith, Sharon L
%A Rogers, Naomi L
%A Ip, Tony K C
%A Hermens, Daniel F
%A Scott, Elizabeth M
%A Hickie, Ian B
%T Delayed sleep phase in young people with unipolar or bipolar affective disorders.
%B Journal of Affective Disorders
%D 2013
%C Netherlands
%I Elsevier BV
%V 145
%N 2
%P 260-263
%@ 0165-0327
%X BACKGROUND: Circadian disturbances may play a key role in the pathogenesis of some forms of mood disorders. Despite marked changes in circadian rhythms during the normal course of adolescence and young adulthood, less is known about changes in the 24-h sleep-wake cycle in young persons with mood disorders. METHODS: Seventy-five young participants with mood disorders (unipolar: n=46, 20.1??4.7 years old; bipolar I or II: n=29, 23.2??4.3) and 20 healthy participants (24.8??2.5 years old) underwent actigraphy monitoring during a depressive phase over seven consecutive days and nights. Sleep phase delay was defined as mean sleep onset ???1:30am and/or sleep offset ???10:00am. RESULTS: A delayed sleep phase was found in 62% of participants with bipolar disorders when depressed, compared with 30% of those with unipolar depression (??(2)=6.0, p=0.014) and 10% of control participants (??(2)=11.2, p<0.001). Sleep offset times were significantly later in subjects with mood disorders compared to the control group, and later in those with bipolar as compared with unipolar disorders (all p???0.043). LIMITATIONS: This study was cross-sectional and the depressed groups were somewhat younger compared to the healthy controls. Longitudinal studies are required to determine the predictive significance of these findings. CONCLUSIONS: Young patients with mood disorders, especially those with bipolar disorders, are particularly likely to have a delayed sleep phase. Therapies focused on advancing sleep phase may be of specific benefit to these young persons.
%Z FOR Codes: 170109


%0 Journal Article
%~ PubMed
%A Scott, Elizabeth M
%A Hermens, Daniel F
%A Naismith, Sharon L
%A Guastella, Adam J
%A De Regt, Tamara
%A White, Django
%A Lagopoulos, Jim
%A Hickie, Ian B
%T Distinguishing young people with emerging bipolar disorders from those with unipolar depression.
%B Journal of Affective Disorders
%D 2013
%C Netherlands
%I Elsevier BV
%V 144
%N 3
%P 208-215
%@ 0165-0327
%X BACKGROUND: To facilitate early intervention, there is a need to distinguish unipolar versus bipolar illness trajectories in adolescents and young adults with adult-type mood disorders. METHODS: Detailed clinical and neuropsychological evaluation of 308 young persons (aged 12 to 30 years) with moderately severe unipolar and bipolar affective disorders. RESULTS: Almost 30% (90/308) of young people (mean age=19.4??4.4yr) presenting for care with affective disorders met criteria for a bipolar-type syndrome (26% with bipolar I). Subjects with bipolar- and unipolar-type syndromes were of similar age (19.8 vs. 19.2yr) and reported comparable ages of onset (14.5 vs. 14.3yr). Clinically, those subjects with unipolar and bipolar-type disorders reported similar levels of psychological distress, depressive symptoms, current role impairment, neuropsychological dysfunction and alcohol or other substance misuse. Subjects with unipolar disorders reported more social anxiety (p<0.01). Subjects with bipolar disorders were more likely to report a family history of bipolar (21% vs. 11%; [??(2)=4.0, p<.05]) or psychotic (19% vs. 9%; [??(2)=5.5, p<.05]), or substance misuse (35% vs. 23%; [??(2)=3.9, p<.05]), but not depressive (48% vs. 53%; ??(2)=0.3, p=.582]) disorders. CONCLUSIONS: Young subjects with bipolar disorders were best discriminated by a family history of bipolar, psychotic or substance use disorders. Early in the course of illness, clinical features of depression, or neuropsychological function, do not readily differentiate the two illness trajectories.
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Hermens, Daniel F
%A Scott, Elizabeth M
%A White, Django
%A Lynch, Marta
%A Lagopoulos, Jim
%A Whitwell, Bradley G
%A Naismith, Sharon L
%A Hickie, Ian B
%T Frequent alcohol, nicotine or cannabis use is common in young persons presenting for mental healthcare: a cross-sectional study.
%B BMJ open
%D 2013
%C United Kingdom
%I BMJ Group
%V 3
%N 2
%P e002229
%@ 2044-6055
%X 
%Z FOR Codes: 110319 111714


%0 Journal Article
%~ PubMed
%A Hickie, Ian B
%A Naismith, Sharon L
%A Robillard, Rébecca
%A Scott, Elizabeth M
%A Hermens, Daniel F
%T Manipulating the sleep-wake cycle and circadian rhythms to improve clinical management of major depression.
%B BMC Medicine
%D 2013
%C United Kingdom
%I BioMed Central Ltd.
%V 11
%N 1
%P 79
%@ 1741-7015
%X 
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Lagopoulos, J
%A Hermens, D F
%A Hatton, S N
%A Battisti, R A
%A Tobias-Webb, J
%A White, D
%A Naismith, S L
%A Scott, E M
%A Ryder, W J
%A Bennett, M R
%A Hickie, I B
%T Microstructural white matter changes are correlated with the stage of psychiatric illness.
%B Translational Psychiatry
%D 2013
%C United Kingdom
%I Nature Publishing Group
%V 3
%N 
%P e248
%@ 2158-3188
%X 
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Lagopoulos, Jim
%A Hermens, Daniel F
%A Hatton, Sean N
%A Tobias-Webb, Juliette
%A Griffiths, Kristi
%A Naismith, Sharon L
%A Scott, Elizabeth M
%A Hickie, Ian B
%T Microstructural white matter changes in the corpus callosum of young people with bipolar disorder: a diffusion tensor imaging study.
%B PloS One
%D 2013
%C United States
%I Public Library of Science
%V 8
%N 3
%P e59108
%@ 1932-6203
%X 
%Z FOR Codes: 110319 110903


%0 Journal Article
%~ PubMed
%A Lee, Rico S C
%A Hermens, Daniel F
%A Redoblado-Hodge, M Antoinette
%A Naismith, Sharon L
%A Porter, Melanie A
%A Kaur, Manreena
%A White, Django
%A Scott, Elizabeth M
%A Hickie, Ian B
%T Neuropsychological and socio-occupational functioning in young psychiatric outpatients: a longitudinal investigation.
%B PloS One
%D 2013
%C United States
%I Public Library of Science
%V 8
%N 3
%P e58176
%@ 1932-6203
%X 
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Hermens, Daniel F
%A Lagopoulos, Jim
%T Pathways to alcohol-induced brain impairment in young people: A review by Hermens et al., 2013: Reply.
%B Cortex
%D 2013
%C Italy
%I Elsevier Masson
%V 49
%N 4
%P 1160-1161
%@ 1973-8102
%X 
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A Hermens, Daniel F
%A Lagopoulos, Jim
%A Tobias-Webb, Juliette
%A De Regt, Tamara
%A Dore, Glenys
%A Juckes, Lisa
%A Latt, Noeline
%A Hickie, Ian B
%T Pathways to alcohol-induced brain impairment in young people: A review.
%B Cortex
%D 2013
%C Italy
%I Elsevier Masson
%V 49
%N 1
%P 3-17
%@ 1973-8102
%X 
%Z FOR Codes: 110904 111716


%0 Journal Article
%~ PubMed
%A Gillespie, Nathan A
%A Henders, Anjali K
%A Davenport, Tracy A
%A Hermens, Daniel F
%A Wright, Margie J
%A Martin, Nicholas G
%A Hickie, Ian B
%T The brisbane longitudinal twin study: pathways to cannabis use, abuse, and dependence project-current status, preliminary results, and future directions.
%B Twin Research and Human Genetics
%D 2013
%C United Kingdom
%I Cambridge University Press
%V 16
%N 1
%P 21-33
%@ 1832-4274
%X 
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Lee, Rico S C
%A Hermens, Daniel F
%A Porter, Melanie A
%A Redoblado-Hodge, M Antoinette
%T A meta-analysis of cognitive deficits in first-episode Major Depressive Disorder.
%B Journal of Affective Disorders
%D 2012
%C Netherlands
%I Elsevier BV
%V 140
%N 2
%P 113-124
%@ 0165-0327
%X BACKGROUND: Recurrent-episode Major Depressive Disorder (MDD) is associated with a number of neuropsychological deficits. To date, less is known about whether these are present in the first-episode. The current aim was to systematically evaluate the literature on first-episode MDD to determine whether cognition may be a feasible target for early identification and intervention. METHODS: Electronic database searches were conducted to examine neuropsychological studies in adults (mean age greater than 18years old) with a first-episode of MDD. Effect sizes were pooled by cognitive domain. Using meta-regression techniques, demographic and clinical factors potentially influencing heterogeneity of neuropsychological outcome were also investigated. RESULTS: The 15 independent samples reviewed yielded data for 644 patients with a mean age of 39.36years (SD=10.21). Significant cognitive deficits were identified (small to medium effect sizes) for psychomotor speed, attention, visual learning and memory, and all aspects of executive functioning. Symptom remission, inpatient status, antidepressant use, age and educational attainment, each significantly contributed to heterogeneity in effect sizes in at least one cognitive domain. LIMITATIONS: Reviewed studies were limited by small sample sizes and often did not report important demographic and clinical characteristics of patients. CONCLUSIONS: The current meta-analysis was the first to systematically demonstrate reduced neuropsychological functioning in first-episode MDD. Psychomotor speed and memory functioning were associated with clinical state, whereas attention and executive functioning were more likely trait-markers. Demographic factors were also associated with heterogeneity across studies. Overall, cognitive deficits appear to be feasible early markers and targets for early intervention in MDD.
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A L, Wang
%A D F, Hermens
%A I B, Hickie
%A J, Lagopoulos
%T A systematic review of resting-state functional-MRI studies in major depression.
%B Journal of Affective Disorders
%D 2012
%C Netherlands
%I Elsevier BV
%V 142
%N 1-3
%P 6-12
%@ 0165-0327
%X 
%Z FOR Codes: 110319 110999 111714


%0 Journal Article
%~ PubMed
%A Naismith, S L
%A Hermens, D F
%A Ip, T K C
%A Bolitho, S
%A Scott, E
%A Rogers, N L
%A Hickie, I B
%T Circadian profiles in young people during the early stages of affective disorder.
%B Translational Psychiatry
%D 2012
%C United Kingdom
%I Nature Publishing Group
%V 2
%N 
%P e123
%@ 2158-3188
%X Although disturbances of the circadian system are strongly linked to affective disorders, no known studies have examined melatonin profiles in young people in early stages of illness. In this study, 44 patients with an affective disorder underwent clinical and neuropsychological assessments. They were then rated by a psychiatrist according to a clinical staging model and were categorized as having an ''attenuated syndrome'' or an ''established disorder''. During the evening, salivary melatonin was sampled under dim light conditions over an 8-h interval and for each patient, the time of melatonin onset, total area under the curve and phase angle (difference between time of melatonin onset and time of habitual sleep onset) were computed. Results showed that there was no difference in the timing of melatonin onset across illness stages. However, area under the curve analyses showed that those patients with ''established disorders'' had markedly reduced levels of melatonin secretion, and shorter phase angles, relative to those with ''attenuated syndromes''. These lower levels, in turn, were related to lower subjective sleepiness, and poorer performance on neuropsychological tests of verbal memory. Overall, these results suggest that for patients with established illness, dysfunction of the circadian system relates clearly to functional features and markers of underlying neurobiological change. Although the interpretation of these results would be greatly enhanced by control data, this work has important implications for the early delivery of chronobiological interventions in young people with affective disorders.
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Perera, Sharnel
%A Crewther, David
%A Croft, Rodney
%A Keage, Hannah
%A Hermens, Daniel
%A Clark, C Richard
%T Comorbid Externalising Behaviour in AD/HD: Evidence for a Distinct Pathological Entity in Adolescence.
%B PLoS One
%D 2012
%C United States
%I Public Library of Science
%V 7
%N 9
%P e41407
%@ 1932-6203
%X 
%Z FOR Codes: 170102


%0 Journal Article
%~ PubMed
%A Hatton, Sean N
%A Lagopoulos, Jim
%A Hermens, Daniel F
%A Naismith, Sharon L
%A Bennett, Maxwell R
%A Hickie, Ian B
%T Correlating anterior insula gray matter volume changes in young people with clinical and neurocognitive outcomes: an MRI study.
%B BMC Psychiatry
%D 2012
%C United Kingdom
%I BioMed Central Ltd.
%V 12
%N 1
%P 45
%@ 1471-244X
%X ABSTRACT: BACKGROUND: The anterior insula cortex is considered to be both the structural and functional link between experience, affect, and behaviour. Magnetic resonance imaging (MRI) studies have shown changes in anterior insula gray matter volume (GMV) in psychosis, bipolar, depression and anxiety disorders in older patients, but few studies have investigated insula GMV changes in young people. This study examined the relationship between anterior insula GMV, clinical symptom severity and neuropsychological performance in a heterogeneous cohort of young people presenting for mental health care. RESULTS: Compared to healthy participants, patients had significantly reduced GMV in the left anterior insula (t=2.05, p=.042) which correlated with reduced performance on a neuropsychological task of attentional set-shifting (rho=0.32, p=.016). Changes in right anterior insula GMV was correlated with increased symptom severity (r=.29, p=.006) and more positive symptoms (r=.32, p=.002). CONCLUSIONS: By using the novel approach of examining a heterogeneous cohort of young depression, anxiety, bipolar and psychosis patients together, this study has demonstrated that insula GMV changes are associated with neurocognitive deficits and clinical symptoms in such young patients.
%Z FOR Codes: 110319 110902 170101


%0 Journal Article
%~ PubMed
%A Pesa, Nicole
%A Hermens, Daniel F
%A Battisti, Robert A
%A Kaur, Manreena
%A Hickie, Ian B
%A Solowij, Nadia
%T Delayed preattentional functioning in early psychosis patients with cannabis use.
%B Psychopharmacology
%D 2012
%C Germany
%I Springer
%V 222
%N 3
%P 507-518
%@ 0033-3158
%X RATIONALE: Cannabis use is prevalent among the early psychosis (EP) population. The event-related potentials, mismatch negativity (MMN) and P3a are reduced in EP. Cannabinoids have been shown to modulate N-methyl-D-aspartate receptors which are involved in MMN generation. OBJECTIVES: This study is the first to investigate the effects of cannabis use on MMN/P3a in EP. METHODS: EP was defined as a history of psychosis or psychotic symptoms with no progression to date to chronic schizophrenia. Twenty-two EP patients with cannabis use (EP?+?CANN), 22 non-cannabis-using EP patients (EP-CANN) and 21 healthy controls participated in this study. MMN/P3a was elicited using a two-tone, auditory paradigm with 8% duration deviants. RESULTS: As expected, EP-CANN showed marked reductions in MMN/P3a amplitudes compared to controls. However, EP?+?CANN showed evidence of a different pattern of neurophysiological expression of MMN/P3a compared to non-using patients, most notably in terms of delayed frontal MMN/P3a latencies. CONCLUSIONS: This study provides further evidence that MMN/P3a deficits are present during early psychosis and suggests that this biomarker may have utility in differentiating substance- from non-substance-related psychoses.
%Z FOR Codes: 170101 110903 110319


%0 Journal Article
%~ PubMed
%A Hermens, D F
%A Lagopoulos, J
%A Naismith, S L
%A Tobias-Webb, J
%A Hickie, I B
%T Distinct neurometabolic profiles are evident in the anterior cingulate of young people with major psychiatric disorders.
%B Translational Psychiatry
%D 2012
%C United Kingdom
%I Nature Publishing Group
%V 2
%N 
%P e110
%@ 2158-3188
%X 
%Z FOR Codes: 110319 110902


%0 Journal Article
%A Sumich, Alexander
%A Sarkar, Sagari
%A Hermens, Daniel
%A Kelesidi, Katerina
%A Taylor, Eric
%A Rubia, Katya
%T Electrophysiological correlates of CU traits show abnormal regressive maturation in adolescents with conduct problems
%B Personality and Individual Differences
%D 2012
%C United Kingdom
%I Pergamon
%V 53
%N 7
%P 862-867
%@ 0191-8869
%X 
%Z FOR Codes: 110319 110999


%0 Journal Article
%~ PubMed
%A Lagopoulos, Jim
%A Hermens, Daniel F
%A Naismith, Sharon L
%A Scott, Elizabeth M
%A Hickie, Ian B
%T Frontal lobe changes occur early in the course of affective disorders in young people.
%B BMC psychiatry
%D 2012
%C United Kingdom
%I BioMed Central Ltd.
%V 12
%N 1
%P 4
%@ 1471-244X
%X ABSTRACT:
%Z FOR Codes: 170101 110903


%0 Journal Article
%~ PubMed
%A Kaur, Manreena
%A Lagopoulos, Jim
%A Ward, Philip B
%A Watson, Tamara L
%A Naismith, Sharon L
%A Hickie, Ian B
%A Hermens, Daniel F
%T Mismatch negativity/p3a complex in young people with psychiatric disorders: a cluster analysis.
%B PLoS One
%D 2012
%C United States
%I Public Library of Science
%V 7
%N 12
%P e51871
%@ 1932-6203
%X 
%Z FOR Codes: 110319 170101


%0 Journal Article
%~ PubMed
%A Kaur, Manreena
%A Battisti, Robert A
%A Lagopoulos, Jim
%A Ward, Philip B
%A Hickie, Ian B
%A Hermens, Daniel F
%T Neurophysiological biomarkers support bipolar-spectrum disorders within psychosis cluster.
%B Journal of Psychiatry & Neuroscience
%D 2012
%C Canada
%I Canadian Medical Association
%V 37
%N 5
%P 313-321
%@ 1488-2434
%X 
%Z FOR Codes: 110904


%0 Journal Article
%~ PubMed
%A Mowszowski, Loren
%A Hermens, Daniel F
%A Diamond, Keri
%A Norrie, Louisa
%A Hickie, Ian B
%A Lewis, Simon J G
%A Naismith, Sharon L
%T Reduced Mismatch Negativity in Mild Cognitive Impairment: Associations with Neuropsychological Performance.
%B Journal of Alzheimer's Disease
%D 2012
%C Netherlands
%I I O S Press
%V 30
%N 1
%P 209-219
%@ 1875-8908
%X Mild cognitive impairment (MCI) refers to a transitory state between healthy aging and dementia. Biomarkers are needed to facilitate early identification of MCI and predict progression to dementia. One potential neurophysiological biomarker, mismatch negativity (MMN), is an event-related potential reflecting fundamental, pre-attentive cognitive processes. MMN is reduced in normal aging and dementia and in neuropsychiatric samples and is associated with verbal memory deficits and poor executive functioning. This study aimed to investigate auditory MMN and its relationship to neuropsychological performance in MCI. Twenty-eight MCI participants and fourteen controls, aged ? 50 years, underwent neurophysiological and neuropsychological assessment, and completed questionnaires pertaining to disability. Relative to controls, the MCI group demonstrated reduced temporal MMN amplitude (p < 0.01). Reduced right temporal MMN was significantly associated with poorer verbal learning (r = 0.496; p < 0.01) and reduced left temporal MMN was significantly associated with increased self-reported disability (r = -0.419; p < 0.05). These results indicate that patients with MCI exhibit altered pre-attentive information processing, which in turn is associated with memory and psychosocial deficits. These findings overall suggest that MMN may be a viable neurophysiological biomarker of underlying disease in this ''at risk'' group.
%Z FOR Codes: 110319 170101 110903


%0 Journal Article
%~ PubMed
%A Naismith, Sharon L
%A Mowszowski, Loren
%A Ward, Philip B
%A Diamond, Keri
%A Paradise, Matthew
%A Kaur, Manreena
%A Lewis, Simon J G
%A Hickie, Ian B
%A Hermens, Daniel F
%T Reduced temporal mismatch negativity in late-life depression: An event-related potential index of cognitive deficit and functional disability?
%B Journal of Affective Disorders
%D 2012
%C Netherlands
%I Elsevier BV
%V 138
%N 1-2
%P 71-78
%@ 0165-0327
%X BACKGROUND: Depression in older people has been consistently linked with a variety of neurobiological brain changes. One measure of preattentive auditory processing, the mismatch negativity (MMN), has not been previously examined in late-life depression. This study examined MMN elicited by duration deviant stimuli in older people with lifetime depression, and explored its relationship with neuropsychological functioning and disability. METHODS: Twenty-two older health-seeking patients (mean age=65.2years) with lifetime major depressive disorder and twelve age and sex-matched control participants (mean age=64.6years) completed detailed clinical and neuropsychological assessments and the WHO-DAS as a measure of disability. MMN amplitudes were elicited using a two-tone passive auditory oddball paradigm and measured at frontal (Fz), central (Cz) and temporal (left and right mastoid: M1 and M2, respectively) sites. RESULTS: Patients with depression demonstrated reduced mean MMN amplitude at temporal (M1, t=3.1, p<0.01; M2, t=3.8, p<0.01), but not fronto-central sites. Reduced temporal MMN amplitudes did not relate to depressive symptom severity, but were associated with reduced semantic fluency and greater self-rated functional disability. LIMITATIONS: The contribution of depressive symptom ''state'' and medications on MMN need to be considered. CONCLUSIONS: Reduced mean amplitudes of mastoid MMN in older patients with lifetime depression may reflect underlying brain changes. This preattentive marker relates to neuropsychological probes of frontotemporal circuits, and importantly, is associated with disability. Longitudinal analysis of MMN in this group will determine its predictive utility as a biomarker for ongoing cognitive decline and illness chronicity.
%Z FOR Codes: 170101 110319 110903


%0 Journal Article
%~ PubMed
%A Sumich, Alexander L
%A Sarkar, Sagari
%A Hermens, Daniel F
%A Ibrahimovic, Almira
%A Kelesidi, Katerina
%A Wilson, Daniel
%A Rubia, Katya
%T Sex differences in brain maturation as measured using event-related potentials.
%B Developmental Neuropsychology
%D 2012
%C United States
%I Psychology Press
%V 37
%N 5
%P 415-433
%@ 1532-6942
%X Little is known about how sex influences functional brain maturation. The current study investigated sex differences in the maturation of event-related potential (ERP) amplitudes during an auditory oddball task (N = 170; age = 6-17 years). Performance improved with age. N200 amplitude declined with age: parietal sites showed earlier development than temporal and frontal locations. Girls showed greater bilateral frontal P300 amplitude development, approaching the higher values observed in boys during childhood. After controlling for age, right frontal P300 amplitude was associated with reaction time in girls. The findings demonstrate sex differences in ERP maturation in line with behavioral and neuroimaging studies.
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A Scott, Elizabeth M
%A Hermens, Daniel F
%A Glozier, Nicholas
%A Naismith, Sharon L
%A Guastella, Adam J
%A Hickie, Ian B
%T Targeted primary care-based mental health services for young Australians.
%B Medical Journal of Australia
%D 2012
%C Australia
%I Australasian Medical Publishing Company Pty. Ltd.
%V 196
%N 2
%P 136-140
%@ 1326-5377
%X To assess the extent to which youth-specific, mental health care centres engage young people (12-25 years of age) in treatment, and to report the degree of psychological distress, and the diagnostic type, stage of illness, and psychosocial and vocational impairment evident in these young people.
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Hickie, Ian B
%A Hermens, Daniel F
%A Scott, Elizabeth M
%T Targeted primary care-based mental health services for young Australians.
%B Medical Journal of Australia
%D 2012
%C Australia
%I Australasian Medical Publishing Company Pty. Ltd.
%V 196
%N 10
%P 627
%@ 1326-5377
%X 
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Scott, Elizabeth M
%A Hermens, Daniel F
%A Naismith, Sharon L
%A White, Django
%A Whitwell, Bradley
%A Guastella, Adam J
%A Glozier, Nick
%A Hickie, Ian B
%T Thoughts of death or suicidal ideation are common in young people aged 12 to 30 years presenting for mental health care.
%B BMC Psychiatry
%D 2012
%C United Kingdom
%I BioMed Central Ltd.
%V 12
%N 1
%P 234
%@ 1471-244X
%X 
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Norberg, Melissa M
%A Battisti, Robert A
%A Copeland, Jan
%A Hermens, Daniel F
%A Hickie, Ian B
%T Two Sides of the Same Coin: Cannabis Dependence and Mental Health Problems in Help-Seeking Adolescent and Young Adult Outpatients.
%B International Journal of Mental Health and Addiction
%D 2012
%C United States
%I Springer New York LLC
%V 10
%N 6
%P 818-828
%@ 1557-1874
%X 
%Z FOR Codes: 110319


%0 Journal Article
%~ PubMed
%A Tsang, Tracey W
%A Kohn, Michael R
%A Hermens, Daniel F
%A Clarke, Simon D
%A Clark, C Richard
%A Efron, Daryl
%A Cranswick, Noel
%A Lamb, Chris
%A Williams, Leanne M
%T A randomized controlled trial investigation of a non-stimulant in attention deficit hyperactivity disorder (ACTION): Rationale and design.
%B Trials
%D 2011
%C United Kingdom
%I BioMed Central Ltd
%V 12
%N 
%P 77
%@ 1745-6215
%X ABSTRACT:
%Z FOR Codes: 1103


%0 Journal Article
%~ PubMed
%A Chitty, Kate M
%A Kaur, Manreena
%A Lagopoulos, Jim
%A Hickie, Ian B
%A Hermens, Daniel F
%T Alcohol use and mismatch negativity in young patients with psychotic disorder.
%B Neuroreport
%D 2011
%C United States
%I Lippincott Williams & Wilkins
%V 22
%N 17
%P 918-22
%@ 0959-4965
%X Mismatch negativity (MMN) is a neurophysiological indicator of the brain''s ability to extract relevant information from an irrelevant background. MMN has been described as a reliable biomarker of schizophrenia and more recently it has found to be impaired in the early stages of psychosis. In addition, drugs (including alcohol) that block glutamate''s N-methyl-D-aspartate receptor have been shown to reduce MMN. This study aims to determine whether risky alcohol consumption in young patients with psychotic disorder further impacts or changes their MMN response. Patients with high-alcohol use were found to show reduced temporal MMN amplitudes compared with patients with low-alcohol use and controls. In contrast, early psychosis patients with low-alcohol use showed reduced fronto-central MMN amplitudes compared with controls; whereas patients with high-alcohol use showed an intermediate response at these sites. Correlational analysis revealed distinct patterns of association between MMN and alcohol use in patients with early psychosis compared with controls. This study shows that early psychosis outpatients who engaged in risky drinking have decreased temporal MMN amplitudes, compared with their peers. This may reflect an additive effect of N-methyl-D-aspartate receptor hypofunction and high-alcohol consumption.
%Z FOR Codes: 110399


%0 Journal Article
%~ PubMed
%A Chudleigh, Catherine
%A Naismith, Sharon L
%A Blaszczynski, Alex
%A Hermens, Daniel F
%A Hodge, M Antoinette Redoblado
%A Hickie, Ian B
%T How does social functioning in the early stages of psychosis relate to depression and social anxiety?
%B Early intervention in psychiatry
%D 2011
%C Australia
%I Wiley-Blackwell Publishing Asia
%V 5
%N 3
%P 224-32
%@ 1751-7893
%X The study aims to compare social functioning in young people considered to be at risk of psychosis with those meeting criteria for first episode psychosis (FEP) and controls, and to determine the association between social functioning and positive and negative symptoms, depressive symptoms, and social anxiety.
%Z FOR Codes: 110319 170113


%0 Journal Article
%~ PubMed
%A Kaur, Manreena
%A Battisti, Robert A
%A Ward, Philip B
%A Ahmed, Arnab
%A Hickie, Ian B
%A Hermens, Daniel F
%T MMN/P3a deficits in first episode psychosis: Comparing schizophrenia-spectrum and affective-spectrum subgroups.
%B Schizophrenia Research
%D 2011
%C Netherlands
%I Elsevier BV
%V 130
%N 1-3
%P 203-209
%@ 0920-9964
%X Reduced mismatch negativity (MMN) and P3a amplitudes are neurophysiological biomarkers for schizophrenia that index deviance detection and the orienting response, respectively. First-episode psychosis (FEP) patients show reduced amplitudes of the ''MMN/P3a complex'', but it is unclear whether this occurs across the FEP spectrum.
%Z FOR Codes: 170101 110319 110903


%0 Journal Article
%~ PubMed
%A Hermens, Daniel F
%A Redoblado Hodge, M Antoinette
%A Naismith, Sharon L
%A Kaur, Manreena
%A Scott, Elizabeth
%A Hickie, Ian B
%T Neuropsychological Clustering Highlights Cognitive Differences In Young People Presenting With Depressive Symptoms.
%B Journal of the International Neuropsychological Society : JINS
%D 2011
%C United Kingdom, Unit
%I Cambridge University Press
%V 17
%N 2
%P 267-76
%@ 1469-7661
%X Early stages of affective or psychotic disorders may be accompanied by neuropsychological changes that help to predict risk of developing more severe disorders. A comprehensive set of neuropsychological measures was collected in 109 help-seeking young people (16 to 30 years; 54 females), recently diagnosed with an affective or psychotic disorder and presenting with current depression. Hierarchical cluster analysis determined three clusters: one deemed to have a "poor memory" profile (n = 40); another with a "poor mental flexibility" profile (n = 38) and a third with widespread difficulties plus "impaired attention and memory" (n = 31). In general, the three clusters were comparable in demographic, functional and clinical factors suggesting some unique role for neurocognitive impairments. A discriminant function analysis confirmed that the clusters were best characterized by performance in "attentional" versus "learning/memory" measures. Furthermore, profiles of independent neuropsychological variables validated the original solution for two of the clusters, distinguishing all cluster-groups on an attentional measure. The findings of this study suggest that despite presenting with very similar levels of current depressive symptomatology, young help-seeking individuals in the early stages of illness have underlying neuropsychological heterogeneity. Distinct neuropsychological profiling may help to predict later psychiatric outcomes and enhance individually-tailored early intervention strategies.
%Z FOR Codes: 170101 110319


%0 Journal Article
%~ PubMed
%A Fallahpour, Kamran
%A Clarke, Simon D
%A Goldberg, Elkhonon
%A Hermens, Daniel F
%A Falconer, Erin M
%A Gordon, Evian
%T Alterations in theta activity associated with novelty and routinization processing in ADHD.
%B Clinical Neurophysiology
%D 2010
%C Ireland
%I Elsevier Ireland Ltd
%V 121
%N 8
%P 1336-1342
%@ 1872-8952
%X OBJECTIVE: Novelty and routinization-related information processing disturbances were examined in adolescent males with ADHD using an oddball paradigm and electrophysiological measurement of theta (4-7Hz) activity. METHODS: Fifty-four unmedicated adolescent males (12-18years) with Attention Deficit Hyperactivity Disorder (ADHD) and matched controls performed an auditory oddball task. Theta activity was sub-averaged, and Fourier Integrals with simultaneous measurement of electrodermal activity (EDA) was used to index response to stimulus novelty and routinization. RESULTS: ADHD participants showed an overall increase in theta activity to both novel and routine stimuli relative to controls. While controls showed increased theta activity in response to novel compared to routine targets across the brain, ADHD participants did not show this novelty-related increase in theta activity in the right anterior/frontal brain. CONCLUSIONS: The findings of this study are consistent with disturbances in theta activity and the brain substrates of novelty relative to routinization-related processing in ADHD. SIGNIFICANCE: These findings show that there are distinct alterations in theta activity related to stimulus novelty and routinization during an auditory oddball task in ADHD, and they highlight the value of using an event-related approach to elucidate the neural substrates of stimulus processing in ADHD.
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A Battisti, Robert A
%A Roodenrys, Steven
%A Johnstone, Stuart J
%A Pesa, Nicole
%A Hermens, Daniel F
%A Solowij, Nadia
%T Chronic cannabis users show altered neurophysiological functioning on Stroop task conflict resolution.
%B Psychopharmacology
%D 2010
%C Germany
%I Springer
%V 212
%N 4
%P 613-624
%@ 0033-3158
%X RATIONALE: Chronic cannabis use has been related to deficits in cognition (particularly memory) and the normal functioning of brain structures sensitive to cannabinoids. There is increasing evidence that conflict monitoring and resolution processes (i.e. the ability to detect and respond to change) may be affected. OBJECTIVES: This study examined the ability to inhibit an automatic reading response in order to activate a more difficult naming response (i.e. conflict resolution) in a variant of the discrete trial Stroop colour-naming task. METHODS: Event-related brain potentials to neutral, congruent and incongruent trials were compared between 21 cannabis users (mean 16.4 years of near daily use) in the unintoxicated state and 19 non-using controls. RESULTS: Cannabis users showed increased errors on colour-incongruent trials (e.g. "RED" printed in blue ink) but no performance differences from controls on colour congruent (e.g. "RED" printed in red ink) or neutral trials (e.g. "*****" printed in green ink). Poorer incongruent trial performance was predicted by an earlier age of onset of regular cannabis use. Users showed altered expression of a late sustained potential related to conflict resolution, evident by opposite patterns of activity between trial types at midline and central sites, and altered relationships between neurophysiological and behavioural outcome measures not evident in the control group. CONCLUSIONS: These findings indicate that chronic use of cannabis may impair the brain''s ability to respond optimally in the presence of events that require conflict resolution and hold implications for the ability to refrain from substance misuse and/or maintain substance abstention behaviours.
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A Battisti, Robert A
%A Roodenrys, Steven
%A Johnstone, Stuart J
%A Respondek, Colleen
%A Hermens, Daniel F
%A Solowij, Nadia
%T Chronic use of cannabis and poor neural efficiency in verbal memory ability.
%B Psychopharmacology
%D 2010
%C Germany
%I Springer
%V 209
%N 4
%P 319-330
%@ 0033-3158
%X INTRODUCTION: The endogenous cannabinoid system is sensitive to the introduction of exogenous cannabinoids such as delta-9-tetrahydrocannabinol, which are known to impact upon memory functioning. We sought to examine the impact of chronic cannabis use upon memory-related brain function via examination of the subsequent memory effect (SME) of the event-related potential (ERP). METHODS: The SME is predictive of recall outcome and originates in structures that are dense with cannabinoid receptors (hippocampus and parahippocampus). The SME and performance on a verbal memory task were compared between 24 cannabis users (mean 17 years of near daily use) in the unintoxicated state and 24 non-using controls. The task involved the presentation of word lists, each with a short delay before recall. ERPs were recorded during encoding and later averaged by outcome (correctly recalled/not recalled). RESULTS: Cannabis users showed poorer recall and altered patterns of SME activation: specifically, attenuation of the negative N4 and an increase in the late positive component. Duration of cannabis use and age of initial use correlated significantly with SME amplitudes. A longer history of use also correlated with greater recall that was related to N4 expression. DISCUSSION: The results indicate that relative to non-using controls, chronic users of cannabis have altered memory-related brain activation in the form of dysfunctional SME production and/or poorer neural efficiency, which is associated with deficits in memory recall. Greater alteration was associated with a longer history of cannabis use and an earlier onset of use. Neuroadaptation to the effects of chronic exposure may additionally play a role.
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A Hermens, Daniel F
%A Ward, Philip B
%A Hodge, M Antoinette Redoblado
%A Kaur, Manreena
%A Naismith, Sharon L
%A Hickie, Ian B
%T Impaired MMN/P3a complex in first-episode psychosis: Cognitive and psychosocial associations.
%B Progress in neuro-psychopharmacology & biological psychiatry
%D 2010
%C United States, Canad
%I Elsevier Inc.
%V 34
%N 6
%P 822-9
%@ 1878-4216
%X Mismatch negativity (MMN) is a neurophysiological indicator of the brain''s ability to extract relevant information from an irrelevant background. The P3a orienting response often accompanies MMN in deviance detection paradigms. Both MMN and P3a have been described as reliable biomarkers of schizophrenia. MMN/P3a impairments are associated with deficits in verbal memory and attentional switching, reflecting dysfunctions in the temporal and frontal systems, respectively. It remains unresolved whether MMN/P3a are robust biomarkers of psychosis in first-episode patients. Thirty-four young people (18 to 30years) were assessed in this study; 17 first-episode psychosis (FEP) patients were compared to 17 healthy controls. To elicit MMN/P3a, a two-tone passive auditory oddball paradigm with 8% duration deviants was used; event-related potentials were recorded at frontal, central and temporal (mastoid) sites. Neuropsychological assessments included processing speed, attentional switching, simple attention, and verbal learning and memory. Social functioning and quality of life measures were also obtained. The FEP group showed significantly reduced MMN amplitudes compared to controls. The FEP group also showed significantly reduced P3a amplitudes at frontal and central sites compared with controls. As expected, the FEP group also showed significant deficits in attention and verbal learning/memory. Correlational analyses found strong associations between fronto-central MMN/P3a peak amplitude and cognitive/psychosocial functioning. This study provides evidence of early neurobiological markers in young people with FEP. These findings suggest that MMN/P3a impairments are present at early stages of psychosis and that fundamental pre-attentive/deviance detection deficits may mark the beginning of progressive underlying changes with illness onset. Such deficits in FEP appear to have important links with higher-order cognitive and psychosocial functioning.
%Z FOR Codes: 1109 1701


%0 Journal Article
%~ PubMed
%A Hermens, Daniel F
%A Naismith, Sharon L
%A Redoblado Hodge, M Antoinette
%A Scott, Elizabeth M
%A Hickie, Ian B
%T Impaired verbal memory in young adults with unipolar and bipolar depression.
%B Early Intervention in Psychiatry
%D 2010
%C Australia
%I Wiley-Blackwell Publishing Asia
%V 4
%N 3
%P 227-233
%@ 1751-7893
%X Aim: Early stages of severe mood disorders may be accompanied by neurocognitive changes. Specifically, deficits in verbal memory have been linked to depression in young people. This study examined whether young adults with unipolar compared with bipolar depression showed similar neurocognitive deficits. Methods: A total of 57 young adults (16-32 years) were assessed in this study. Twenty with unipolar and 20 with bipolar depression, all currently depressed, were compared with 17 healthy controls. Neuropsychological assessment included psychomotor speed, attention for routine mental operations, attentional switching, executive control and verbal learning and memory. Results: Both unipolar and bipolar subjects showed significant impairments in verbal memory and attentional switching compared with controls. Both mood disorder groups showed no impairments in psychomotor speed, attention for routine mental operations and executive control. Effects size calculations show that the unipolar and bipolar groups do not differ from each other across a range of neurocognitive measures. Conclusion: Neurocognitive deficits in young adults with current depressive syndromes appear to differ from those typically seen in older patients. In early adulthood, both unipolar and bipolar depression may be distinguished by poor verbal memory, despite intact speed of processing, attention and executive functions. This study suggests that there is utility in neuropsychological testing for young adults in the early stages of severe mood disorders. In order to prevent neurobiological changes inherent to the disease, pharmacological and non-pharmacological interventions that target verbal memory deficits may be optimally delivered early in the disease course.
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A Williams, Leanne M
%A Hermens, Daniel F
%A Thein, Thida
%A Clark, C Richard
%A Cooper, Nicholas J
%A Clarke, Simon D
%A Lamb, Chris
%A Gordon, Evian
%A Kohn, Michael R
%T Using brain-based cognitive measures to support clinical decisions in ADHD.
%B Pediatric Neurology
%D 2010
%C United States
%I Elsevier Inc.
%V 42
%N 2
%P 118-126
%@ 1873-5150
%X Measures of cognition support diagnostic and treatment decisions in attention deficit hyperactivity disorder. We used an integrative neuroscience framework to assess cognition and associated brain-function correlates in large attention deficit hyperactivity disorder and healthy groups. Matched groups of 175 attention deficit hyperactivity disorder children/adolescents and 175 healthy control subjects were assessed clinically, with the touch screen-based cognitive assessment battery "IntegNeuro" (Brain Resource Ltd., Sydney, Australia) and the "LabNeuro" (Brain Resource Ltd., Sydney, Australia) platform for psychophysiologic recordings of brain function and body arousal. IntegNeuro continuous performance task measures of sustained attention classified 68% of attention deficit hyperactivity disorder patients with 76% specificity, consistent with previous reports. Our additional cognitive measures of impulsivity, intrusive errors, inhibition, and response variability improved sensitivity to 88%, and specificity to 91%. Positive predictive power was 96%, and negative predictive power, 88%. These metrics were stable across attention deficit hyperactivity disorder subtypes and age. Consistent with their brain-based validity, cognitive measures were correlated with corresponding brain-function and body-arousal measures. We propose a combination of candidate cognitive "markers" that define a signature for attention deficit hyperactivity disorder: "sustained attention," "impulsivity," "inhibition," "intrusions," and "response variability." These markers offer a frame of reference to support diagnostic and treatment decisions, and an objective benchmark for monitoring outcomes of interventions.
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A Hermens, Daniel F
%A Lubman, Dan I
%A Ward, Philip B
%A Naismith, Sharon L
%A Hickie, Ian B
%T Amphetamine psychosis: a model for studying the onset and course of psychosis.
%B The Medical Journal of Australia
%D 2009
%C Australia
%I Australasian Medical Publishing Company Pty. Ltd
%V 190
%N 4 Suppl
%P S22-S25
%@ 1326-5377
%X The aetiology of schizophrenia remains complex, although proposed models have identified genetic markers and environmental pathogens as important risk factors. Researchers have found no large-effect or unique genetic elements, and only a small number of putative environmental agents have been identified. Use of amphetamine-type stimulants (ATSs) is an exemplar environmental pathogen, as it is known to trigger schizophrenia-like illness and other psychotic and manic episodes. To date, the ATS model of illness onset has been under-utilised. It has the potential to reveal key neurobiological elements of schizophrenia and related psychoses. The model proposed here has the capacity to inform detection of those at risk of ATS-related psychoses, and therefore help develop early intervention strategies. It is possible that the same approach may be used in young people known to be at risk of schizophrenia and related disorders, by informing models that involve other environmental or genetic risks.
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A Kemp, Andrew H
%A Hopkinson, Patrick J
%A Hermens, Daniel F
%A Rowe, Donald L
%A Sumich, Alexander L
%A Clark, C Richard
%A Drinkenburg, Wilhelmus
%A Abdi, Nadia
%A Penrose, Rebecca
%A McFarlane, Alexander
%A Boyce, Philip
%A Gordon, Evian
%A Williams, Leanne M
%T Fronto-temporal alterations within the first 200 ms during an attentional task distinguish major depression, non-clinical participants with depressed mood and healthy controls: A potential biomarker?
%B Human brain mapping
%D 2009
%C United States
%I John Wiley and Sons
%V 30
%N 2
%P 602-14
%@ 1065-9471
%X Attentional impairment in depression is a cardinal feature of depression and has been proposed as a candidate endophenotype for major depressive disorder. Event-related potentials (ERPs) elicited by oddball signal detection tasks provide objective markers of selective stimulus processing, and are pertinent endophenotypic markers for depression. While previous studies have sought to determine objective markers for attentional impairment in depression, evidence is inconsistent and may involve heterogeneity in relatively small samples. Here, we brought together oddball ERP recording with source localization of neural correlates of selective attention in outpatients with major depressive disorder (MDD; n = 78) and participants with depressed mood (PDM; n = 127) relative to healthy controls (CTL; n = 116). The key finding was a dimensional exaggeration of the P200 (140-270 ms) to both target (signal) and non-target (noise) stimuli, most pronounced in MDD, followed by PDM, relative to CTL. This exaggeration was coupled with slower and more variable response times, suggesting that neural systems are attempting to compensate for a difficulty in discriminating signal from noise. P200 alterations were localised to limbic (hippocampal), temporal and ventral prefrontal regions, key components of the signal detection network. A subsequent reduction and delay in the P300 was also revealed for MDD indicating that the pronounced lack of discrimination in clinical depression may also lead to impaired stimulus evaluation. This P200 increase in depression could provide a potential mechanism for the attentional impairment frequently observed in depression and consequent alterations in the P300 may differentiate clinically significant depression.
%Z FOR Codes: 110999 111714


%0 Journal Article
%~ PubMed
%A Keage, Hannah A D
%A Clark, C Richard
%A Hermens, Daniel F
%A Williams, Leanne M
%A Kohn, Michael R
%A Clarke, Simon
%A Lamb, Christopher
%A Crewther, David
%A Gordon, Evian
%T ERP indices of working memory updating in AD/HD: differential aspects of development, subtype, and medication.
%B Journal of Clinical Neurophysiology
%D 2008
%C United States
%I Lippincott Williams & Wilkins
%V 25
%N 1
%P 32-41
%@ 0736-0258
%X This study investigated whether children and adolescents diagnosed with the predominantly inattentive and combined subtypes of attention deficit/hyperactivity disorder (AD/HD-in and AD/HD-com, respectively) differed on psychophysiological indices of working memory updating off- and on-stimulant medication, as compared with control subjects and each other. ERPs were recorded in AD/HD and control participants during a one-back working memory task. The N100 (discrimination), P150 (selection), N300 (memory retrieval), and P450wm (updating) components after nontarget stimuli, which served to update working memory with target identity, were assessed. Premedication abnormalities were obtained for the N300 component, delayed in the child AD/HD-com group, and attenuated in the adolescent AD/HD-in group and P450wm component for all AD/HD groups, expressed as either delayed latency and/or attenuated amplitude. ERP abnormalities were predominantly ameliorated after stimulant medication. There were no psychophysiological differences between the subtypes. A general feature of the disorder relates to a deficit in the conscious updating of working memory systems with newly relevant information (P450wm), which varies with age and subtype. Children with AD/HD-com and adolescents with AD/HD-in also exhibit abnormalities in the retrieval of relevant prior memories (N300). This study indicates that AD/HD is related to abnormalities in the capacity to modulate the content of working memory stores.
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A Alexander, David M
%A Hermens, Daniel F
%A Keage, Hannah A D
%A Clark, C Richard
%A Williams, Leanne M
%A Kohn, Michael R
%A Clarke, Simon D
%A Lamb, Chris
%A Gordon, Evian
%T Event-related wave activity in the EEG provides new marker of ADHD.
%B Clinical Neurophysiology
%D 2008
%C Ireland
%I Elsevier Ireland Ltd
%V 119
%N 1
%P 163-179
%@ 1388-2457
%X OBJECTIVE: This study examines the utility of new measures of event-related spatio-temporal waves in the EEG as a marker of ADHD, previously shown to be closely related to the P3 ERP in an adult sample. METHODS: Wave activity in the EEG was assessed during both an auditory Oddball and a visual continuous performance task (CPT) for an ADHD group ranging in age from 6 to 18 years and comprising mostly Combined and Inattentive subtypes, and for an age and gender matched control group. RESULTS: The ADHD subjects had less wave activity at low frequencies ( approximately 1 Hz) during both tasks. For auditory Oddball targets, this effect was shown to be related to smaller P3 ERP amplitudes. During CPT, the approximately 1 Hz wave activity in the ADHD subjects was inversely related to clinical and behavioral measures of hyperactivity and impulsivity. CPT wave activity at approximately 1 Hz was seen to "normalise" following treatment with stimulant medication. CONCLUSIONS: The results identify a deficit in low frequency wave activity as a new marker for ADHD associated with levels of hyperactivity and impulsivity. SIGNIFICANCE: The marker is evident across a range of tasks and may be specific to ADHD. While lower approximately 1 Hz activity partly accounts for reduced P3 ERPs in ADHD, the effect also arises for tasks that do not elicit a P3. Deficits in behavioral inhibition are hypothesized to arise from underlying dysregulation of cortical inhibition.
%Z FOR Codes: 110999


%0 Journal Article
%~ PubMed
%A Williams, Leanne M
%A Hermens, Daniel F
%A Palmer, Donna
%A Kohn, Michael
%A Clarke, Simon
%A Keage, Hannah
%A Clark, C Richard
%A Gordon, Evian
%T Misinterpreting emotional expressions in attention-deficit/hyperactivity disorder: evidence for a neural marker and stimulant effects.
%B Biological Psychiatry
%D 2008
%C USA
%I Elsevier
%V 63
%N 10
%P 917-926
%@ 1873-2402
%X BACKGROUND: In addition to cognitive impairment, there are disruptions to mood and emotion processing in attention-deficit/hyperactivity disorder (ADHD) but little is known about their neural basis. We examined ADHD disturbances in mood and emotion recognition and underlying neural systems before and after treatment with stimulant medication. METHODS: Participants were 51 unmedicated ADHD adolescents and 51 matched healthy control subjects rated for depressed and anxious mood and accuracy for identifying facial expressions of basic emotion. Brain function was recorded using event-related potentials (ERPs) while subjects viewed these expressions. ADHD subjects were retested after 4 weeks, following treatment with methylphenidate (MPH). RESULTS: ADHD subjects showed a profile of emotion-related impairment: higher depression and anxiety, deficits in identifying threat-related emotional expressions in particular, and alterations in ERPs. There was a pronounced reduction in occipital activity during the early perceptual analysis of emotional expression (within 120 msec), followed by an exaggeration of activity associated with structural encoding (120-220 msec) and subsequent reduction and slowing of temporal brain activity subserving context processing (300-400 msec). Methylphenidate normalized neural activity and produced some improvement of emotion recognition but had no impact on negative mood. Improvements in neural activity with MPH were consistent predictors of improvement in clinical features of emotional lability and hyperactivity. CONCLUSIONS: Objective behavioral and brain function measures of emotion processing may provide a valuable addition to the clinical armamentarium for assessing emotional disturbances in ADHD and the efficacy of stimulants for treating these disturbances.
%Z FOR Codes: 110999


%0 Journal Article
%~ PubMed
%A Keage, Hannah A D
%A Clark, Christopher R
%A Hermens, Daniel F
%A Williams, Leanne M
%A Kohn, Michael R
%A Clarke, Simon
%A Lamb, Christopher
%A Crewther, David
%A Gordon, Evian
%T Putative biomarker of working memory systems development during childhood and adolescence.
%B Neuroreport
%D 2008
%C United States
%I Lippincott Williams & Wilkins
%V 19
%N 2
%P 197-201
%@ 1473-558X
%X The study aimed to identify brain functional indicators of working memory systems development between 6 and 18 years. Event-related potentials (ERPs) were recorded from 251 normally developing children to stimuli requiring the updating of working memory. Cluster analysis of event-related potential componentry divided the sample into three clusters (mean ages 9, 12 and 16 years), with ascending cluster membership independently associated with improved task performance. The clusters correspond to periods of grey matter loss and white matter increase observed in developing children, supporting the view that the clusters delineate three key qualitative stages in advancing cognitive capability during the maturation of higher brain systems function. This outcome identifies a biomarker with the potential for assessing abnormalities in the rate of brain development.
%Z FOR Codes: 170101


%0 Journal Article
%~ PubMed
%A Hermens, Daniel F
%A Cooper, Nicholas J
%A Clark, C Richard
%A Debrota, David
%A Clarke, Simon D
%A Williams, Leanne M
%T An integrative approach to determine the best behavioral and biological markers of methylphenidate.
%B Journal of integrative neuroscience
%D 2007
%C United Kingdom
%I Imperial College Press
%V 6
%N 1
%P 105-140
%@ 0219-6352
%X AIMS: To distinguish the most sensitive markers of methylphenidate (MPH) effects on behavior and underlying biology using an integrated cognitive and brain function test battery. METHODS: A randomized placebo-controlled trial with 32 healthy adult males. Subjects were tested on MPH doses across 18 sessions with subjective mood, objective behavioral and biological endpoints. From a computerized battery of tests, behavioral measures were cognitive performance scores, while biological measures of brain function included electroencephalographs (EEG) and event-related potentials (ERPs) with complementary measures of autonomic arousal. Using mixed modeling analyses; we determined which measures were most affected by MPH dose and correlation analyses determined the associations among them. RESULTS: MPH dose had the most pronounced effect on cognitive performance (sustained attention/vigilance), baseline autonomic arousal (heart rate, blood pressure) and baseline brain activity (EEG theta power). The faster reaction time, reduced errors, increased autonomic arousal and reductions in theta showed strong to moderate inter-correlations. MPH least affected subjective mood measures and early sensory ERP components. DISCUSSION: These findings suggest that MPH increases cortical and autonomic arousal, facilitating vigilance. The combination of behavioral and biological measures may provide an objective set of markers of MPH response. INTEGRATIVE SIGNIFICANCE: This approach has provided additional insight into the mechanism of the stimulant medication, MPH, which would not be achieved by using such measures in isolation.
%Z FOR Codes:


%0 Journal Article
%~ PubMed
%A Clarke, Simon D
%A Kohn, Michael R
%A Hermens, Daniel F
%A Rabbinge, Maaike
%A Clark, C Richard
%A Gordon, Evian
%A Williams, Leanne M
%T Distinguishing symptom profiles in adolescent ADHD using an objective cognitive test battery.
%B International journal of adolescent medicine and health
%D 2007
%C Israel
%I Freund Publishing House, Ltd.
%V 19
%N 3
%P 355-367
%@ 0334-0139
%X Currently diagnosis and assessment of ADHD relies on clinical interview and subjective ratings. Standardized objective cognitive tests can provide additional information about ADHD and help distinguish symptom profiles. OBJECTIVE: To assess the cognition of adolescent ADHD subtypes using a standardized cognitive test battery. STUDY GROUP: Seventy-two ADHD combined subtype, 58 ADHD predominantly inattentive subtype and 130 age- and sex-matched healthy controls. METHODS: Cognitive differences between ADHD subtypes were examined according to 1. symptom dimensions (inattentive versus hyperactivity/impulsivity scores) and 2. category (ADHDcom vs. ADHDin). We examined whether cognitive performance would discriminate symptom profiles (from each other and from healthy controls), and whether these profiles could predict test performance. All subjects completed the standardized and fully computerized IntegNeuro test battery using a touch-screen protocol. These tests span the domains of sensori-motor, attention, executive function, language and memory, and have robust construct validity compared to traditional paper-and-pencil tests. The results highlighted the consistency with which performance varied across symptom profiles, irrespective of categorical or dimensional definitions. ADHDcom was primarily distinguished from ADHDin by increased errors and response variability in response inhibition and (to a lesser extent) selective attention tasks. Inattentive symptoms were more likely to predict cognitive performance and there is an indication that despite the same criteria, these symptoms may be more severe in the ADHDcom subtype. CONCLUSIONS: These findings highlight the specificity of cognitive deficits, which differentiate ADHD subtypes in adolescence. This study provides consistent evidence that accuracy and response variability in an executive function (response inhibition) task may best distinguish the common ADHD subtypes.
%Z FOR Codes: 110999


%0 Journal Article
%~ PubMed
%A Keage, Hannah A D
%A Clark, C Richard
%A Hermens, Daniel F
%A Kohn, Michael R
%A Clarke, Simon
%A Williams, Leanne M
%A Crewther, David
%A Lamb, Chris
%A Gordon, Evian
%T Distractibility in AD/HD predominantly inattentive and combined subtypes: the P3a ERP component, heart rate and performance.
%B Journal of integrative neuroscience
%D 2007
%C United Kingdom
%I Imperial College Press
%V 5
%N 1
%P 139-58
%@ 0219-6352
%X The current study aimed to investigate whether children and adolescents diagnosed with Attention Deficit/Hyperactivity Disorder Predominantly Inattentive (AD/HD-in; Child n = 24, Adolescent n = 33) and Combined (AD/HD-com; Child n = 30, Adolescent n = 42) subtypes were more distractible than controls (Child n = 54; Adolescents n = 75), by assessing event-related potential (ERP), performance and peripheral arousal measures. All AD/HD groups displayed smaller amplitudes and/or shorter latencies of the P3a ERP component - thought to reflect involuntary attention switching - following task-deviant novel stimuli (checkerboard patterns) embedded in a Working Memory (WM) task. The P3a results suggested that both AD/HD-in and AD/HD-com subtypes ineffectively evaluate deviant stimuli and are hence more "distractible". These abnormalities were most pronounced over the central areas. AD/HD groups did not display any abnormalities in averaged heart rate over the WM task, a measure of peripheral arousal. They did display abnormalities in performance measures from the task, but these were unrelated to P3a abnormalities. AD/HD groups also displayed a number of deficits on Switching of Attention and Verbal Memory tasks, however, the pattern of abnormality mostly reflected general cognitive deficits rather than resulting from distraction.
%Z FOR Codes: 110999


%0 Journal Article
%~ PubMed
%A Gordon, Evian
%A Liddell, Belinda J
%A Brown, Kerri J
%A Bryant, Richard
%A Clark, C Richard
%A DAS, Pritha
%A Dobson-Stone, Carol
%A Falconer, Erin
%A Felmingham, Kim
%A Flynn, Gary
%A Gatt, Justine M
%A Harris, Anthony
%A Hermens, Daniel F
%A Hopkinson, Patrick J
%A Kemp, Andrew H
%A Kuan, Stacey A
%A Lazzaro, Illario
%A Moyle, Jonson
%A Paul, Robert H
%A Rennie, Chris J
%A Schofield, Peter
%A Whitford, Thomas
%A Williams, Leanne M
%T Integrating objective gene-brain-behavior markers of psychiatric disorders.
%B Journal of Integrative Neuroscience
%D 2007
%C United Kingdom
%I Imperial College Press
%V 6
%N 1
%P 1-34
%@ 0219-6352
%X There is little consensus about which objective markers should be used to assess major psychiatric disorders, and predict/evaluate treatment response for these disorders. Clinical practice relies instead on subjective signs and symptoms, such that there is a "translational gap" between research findings and clinical practice. This gap arises from: a) a lack of integrative theoretical models which provide a basis for understanding links between gene-brain-behavior mechanisms and clinical entities; b) the reliance on studying one measure at a time so that linkages between markers are their specificity are not established; and c) the lack of a definitive understanding of what constitutes normative function. Here, we draw on a standardized methodology for acquiring multiple sources of genomic, brain and behavioral data in the same subjects, to propose candidate markers of selected psychiatric disorders: depression, post-traumatic stress disorder, schizophrenia, attention-deficit/hyperactivity disorder and dementia disorders. This methodology has been used to establish a standardized international database which provides a comprehensive framework and the basis for testing hypotheses derived from an integrative theoretical model of the brain. Using this normative base, we present preliminary findings for a number of disorders in relation to the proposed markers. Establishing these objective markers will be the first step towards determining their sensitivity, specificity and treatment prediction in individual patients.
%Z FOR Codes: 110999 60410