European Psychiatry - Volume 33 - March 2016

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S234 24th European Congress of Psychiatry / European Psychiatry 33S (2016) S116–S348
involved in the study. Cortical EEG sources were estimated by stan-
dardized low-resolution electromagnetic tomography (sLORETA)
in seven frequency bands: delta (1.5–6Hz), theta (6.5–8Hz), alpha-
1 (8.5–10Hz), alpha-2 (10.5–12Hz), beta-1 (12.5–18Hz), beta-2
(18.5–21Hz) and beta-3 (21.5–30Hz). Cognitive performance was
measured by the Trail-Making Test (version A and B). Emotional
states were induced by using two different scenarios. One of them
was autobiographical (related to OCD symptoms of the patient) and
the other aimed to induce general anxiety.
Results Our results show different activation during exposure
autobiographical and generally anxiety scenario in patients with
OCD. During the exhibition, generally anxious scenario the activ-
ity changed in temporo-parietal areas both in OCD patients and
healthy controls. Whereas during the exposition to autobiograph-
ical scenario we found activity changes in frontal areas.
Conclusions Our results suggest differences in the activation of
brain structures when exposed to specific and non-specific anxiety
in OCD patients.
Disclosure of interest The authors have not supplied their decla-
ration of competing interest.
EW346
qEEG correlates of cognitive
impairment in obsessive compulsive
patients
D. Kamaradova ∗, J. Prasko , K. Latalova , A. Grambal , J. Taborsky ,
M. Hajda
University Hospital Olomouc, Psychiatry, Olomouc, Czech Republic
∗ Corresponding author.
Introduction Similar to patients with schizophrenia or bipolar
affective disorder many studies demonstrated presence of cogni-
tive impairment in OCD (obsessive-compulsive disorder) patients.
Aim of our study was to identify correlates of cognitive impairment
in OCD patients using quantitative EEG.
Methods Resting-state eyes-closed EEG data were recorded in
twenty OCD patients and fifteen healthy controls that were
involved in the study. Cortical EEG sources were estimated by stan-
dardized low-resolution electromagnetic tomography (sLORETA)in
seven frequency bands: delta (1.5–6Hz), theta (6.5–8Hz), alpha-
1 (8.5–10Hz), alpha-2 (10.5–12Hz), beta-1 (12.5–18Hz), beta-2
(18.5–21Hz) and beta-3 (21.5–30Hz). Cognitive performance was
measured by the Trail-Making Test (version A and B).
Results Frontal delta and theta EEG sources showed significantly
higher activity in the whole group of OCD patients (n = 20) than
in control subjects (n = 15). Subsequent analysis revealed that this
excess of low-frequency activity was present only in the subgroup
of 11 patients with cognitive impairment (based on the perfor-
mance in the Trail Making Test–A). The subgroup of patients with
normal cognitive functions (n = 9) did not differ in cortical EEG
sources from healthy controls.
Conclusion The present results suggest that frontal low-
frequency cortical sources of resting state EEG rhythms can
distinguish groups of cognitively impaired and cognitively intact
OCD patients. Based on our results, future studies should consider
whether the present methodological approach provides clinically
useful information for the revelation of cognitive impairment in
OCD patients.
Disclosure of interest The authors have not supplied their decla-
ration of competing interest.
EW347
The inattentive and hyperactive brain:
Significant links between corpus
callosum features and ADHD
symptoms in adulthood
E. Luders ∗, F. Kurth , D. Das , D. Oyarce , M. Shaw ,
P. Sachdev , S. Easteal , K. Anstey , N. Cherbuin
1 UCLA School of Medicine, Neurology, Los Angeles, USA
2 Australian National University, Centre for Research on Ageing
Health and Wellbeing, Canberra, Australia
3 University of New South Wales, School of Psychiatry, Sydney,
Australia
4 Australian National University, John Curtin School of Medical
Research, Canberra, Australia
∗ Corresponding author.
Introduction Neuroimaging studies of attention-
deficit/hyperactivity disorder (ADHD) have revealed structural
deviations of the corpus callosum in children and adolescents.
However, little is known about the link between callosal morphol-
ogy and symptoms of inattention or hyperactivity in adulthood,
especially later in life.
Objective We aimed to further expand this understudied field
by analyzing a large population-based sample of 280 adults (150
males, 130 females) in their late sixties and early seventies.
Methods We applied a well-validated approach capturing the
thickness of the corpus callosum with a high regional specificity
at 100 equidistant points. In addition to correlating point-wise cal-
losal thickness with ADHD symptom measures within the whole
sample, we tested for sex interactions.
Results There were significant sex interactions with respect to
measures of inattention and hyperactivity, with follow-up analyses
revealing significant negative correlations in males (see –
Top). In contrast, there were positive correlations with respect to
hyperactivity only in females (see Bottom).
Conclusion A thinner corpus callosum may be associated with
fewer fibers or less myelination. Thus, the negative correlations, as
observed inmales, suggest an impaired inter-hemispheric commu-
nication necessary to sustain motor control and attention, which
may contribute to symptoms of hyperactivity, impulsivity and/or
inattention. The functional relevance and underlying mechanisms
of the positive correlations, as detected in females, remain to be
resolved.
Fig. 1