European Psychiatry - Volume 33 - March 2016

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24th European Congress of Psychiatry / European Psychiatry 33S (2016) S116–S348 S235
Disclosure of interest The authors have not supplied their decla-
ration of competing interest.
EW348
Gamma band dysfunction in patients
with schizophrenia during a
Sternberg Task: A wavelet analysis
D.D. Marasco ∗ Di Lorenzo Petito Altamura
G. Francavilla , L. Inverso , A. Bellomo
1 Laboratory of Neurophysiology, Department of Clinical and
Experimental Medicine, Section of Psychiatry, University of Foggia,
Foggia, Italy
2 Laboratory of Psychophysiology, Department of Systems Medicine,
University of Rome “Tor Vergata”, Rome, Italy
∗ Corresponding author.
Background Increasing body of evidence suggest that patients
with schizophrenia (SCZ) present dysfunction of the gamma band
oscillations (GBO) during cognitive tasks. The current study aimed
to explore the GBO activity in SCZ during a Sternberg task.
Materials and methods Twenty-eight chronic stabilized SCZ and
18 healthy controls (HC), were recruited. Ongoing EEG was
recorded during the execution of the Sternberg task. Continu-
ous EEG data were band-pass filtered (1–100Hz) and corrected
for eye blink and muscle artefacts by ICA. For each subject,
the event-related-spectral-perturbation (ERSP) and the inter-trial-
coherence (ITC) were computed at the Pz channel only for
those stimulus-locked segments containing correct responses. GBO
wavelet analysis was performedwith two different increasing cycle
ranges (3 to 5.8 and 12 to 22.6; frequency range: 30–90Hz), to
obtain the best information about temporal and frequency dynam-
ics. Student’s t test (withmultiple comparisons FDR correction) was
used to compare the groups.
Results During the manteinance phase (4000 to 4600ms after
the stimulus onset), SCZ presented a significant increase, respect
to HC, in low GBO activity (range: 30-50Hz;). In the other phases
of the Sternberg task (encoding, probe presentation and response
periods), no significant difference in GBO was observed between
SCZ and HC.
Conclusions These findings are in line with the evidence that GBO
dysfunction in SCZ is present during selective phases of the work-
ing memory task. Future studies have to clarify the role of GBO
dysfunction on the cognitive performance and the clinical utility of
selective GBO modulation during cognitive rehabilitation.
Disclosure of interest The authors have not supplied their decla-
ration of competing interest.
EW349
Sweet and bitter taste perception in
anorexia nervosa: A functional MRI
study
A.M. Monteleone ∗ sposito rinster antone
A. Canna ellegrino Nigro modio Volpe
F. Di Salle onteleon
1 Second University of Naples, Department of Psychiatry, Naples, Italy
2 University of Salerno, Neuroscience Section, Department of
Medicine and Surgery, Salerno, Italy
3 National Research Council, Biostructure and Bioimaging Institute,
Naples, Italy
4 Federico II University, ENT Department, Naples, Italy
∗ Corresponding author.
Introduction Taste perception is a complex phenomenon mod-
ulated by different factors, such as taste receptors and memory
brain circuits. The palatability of the food, that activates the central
reward pathways, also plays an important role in taste perception.
It means that taste is able to influence the choice of food and then
eating behaviour.
Objectives It is well known that people with anorexia nervosa
(AN) have a lower sensitivity to reward stimuli and recent stud-
ies suggested that altered function of taste neural circuitry may
contribute to restricted eating in AN.
Aims The aim of this study was to evaluate, in patients suffering
from AN, the activation of brain areas involved in taste perception
and in central reward mechanisms to both pleasant and aversive
taste stimuli and to correlate gustatory neurocircuitry activity with
eating behaviours, temperament measures and/or sensitivity to
reward and to punishment.
Methods Fifteen underweight female AN patients and sixteen
normal-weight healthy women underwent a functional MRI to
measure brain areas activation to repeated stimuli of a pleasant
taste (sucrose solution), alternated with an aversive taste (bitter
solution), and water taste.
Results Compared to healthy controls, patients with AN showed
a significantly reduced activation of left insula and left dorsolateral
prefrontal cortex to sweet stimulus and reduced activation of right
parietal cortex to bitter stimulus.
Conclusions These results, if confirmed in future studies, may
improve our knowledge about the pathophysiological mechanisms
of AN.
Disclosure of interest The authors have not supplied their decla-
ration of competing interest.
EW350
Implication of altered 7 nicotinic
receptors and amyloid deposition in
the Alzheimer’s brain
K. Nakaizumi ∗ erada oshikawa Kakimoto
I. Takashi uzuk omoyasu uzuki agata
N. Mori uchi
1 Hamamatsu University School of Medicine, Psychiatry, Hamamatsu,
Japan
2 Hamamatsu University School of Medicine, Biofunctional Imaging,
Hamamatsu, Japan
3 Hamamatsu Photonics K.K.- Hamamatsu- Japan, Central Research
Laboratory, Hamamatsu, Japan
4 Hamamatsu University School of Medicine, Molecular Imaging-
Medical Photonics Research Center, Hamamatsu, Japan
∗ Corresponding author.
Introduction Brain amyloid- protein (A ) deposition is a key
pathology of Alzheimer’s disease (AD). Cholinergic degeneration,
including reductions in 7 nicotinic acetylcholine receptors ( 7-
nAChR), is also known as a pathophysiology of AD. Recent imaging
studies have shown cognitively normal subjects with A depo-
sitions, indicating a missing link between A deposition and
cognitive decline.
Objectives To clarify relationships among the A burden, 7-
nAChR availability, and cognitive declines in AD.
Aims To measure brain A deposition and 7-nAChR availability
in the same patients with AD using positron emission tomography
(PET).
Methods Twenty AD patients and age-matched 20 healthy adults
were studied. The 7-nAChR availability and A deposition were
evaluated using PET with [11C]MeQAA and [11C]PIB, respectively.
Levels of specific binding were estimated by a simplified reference
tissue method (BPND) for [ 11C]MeQAA and a tissue ratio method
(SUVR) for using [ 11C]PIB. The values were compared with clinical
measures of various cognitive functions using regions of interest
(ROIs)-based and statistical parametric mapping (SPM) analyses.
Results [11C]MeQAA BPND levels were extensively lower in the
cholinergic projection regions of AD. There was a significant