21 research outputs found
Neural correlates of moral judgment in pedophilia
Pedophilia is a sexual preference that is often associated with child sex
offending (CSO). Sexual urges towards prepubescent children and specifically
acting upon those urges are universally regarded as immoral. However, up until
now, it is completely unknown whether moral processing of sexual offenses is
altered in pedophiles. A total of 31 pedophilic men and 19 healthy controls
were assessed by using functional magnetic resonance imaging (fMRI) in
combination with a moral judgment paradigm consisting of 36 scenarios
describing different types of offenses. Scenarios depicting sexual offenses
against children compared to those depicting adults were associated with
higher pattern of activation in the left temporo-parietal-junction (TPJ) and
left posterior insular cortex, the posterior cingulate gyrus as well as the
precuneus in controls relative to pedophiles, and vice versa. Moreover, brain
activation in these areas were positively associated with ratings of moral
reprehensibility and negatively associated with decision durations, but only
in controls. Brain activation, found in key areas related to the broad network
of moral judgment, theory of mind and (socio-)moral disgust - point to
different moral processing of sexual offenses in pedophilia in general. The
lack of associations between brain activation and behavioral responses in
pedophiles further suggest a biased response pattern or dissected implicit
valuation processes
Aerobic Activity in the Healthy Elderly Is Associated with Larger Plasticity in Memory Related Brain Structures and Lower Systemic Inflammation
Dissociation of behavioral and neural responses to provocation during reactive aggression in healthy adults with high versus low externalization
The externalizing spectrum describes a range of heterogeneous personality traits and behavioral patterns, primarily characterized by antisocial behavior, disinhibition, and substance (mis)use. In psychopathology, abnormalities in neural threat, reward responses and the impulse-control system may be responsible for these externalizing symptoms. Within the non-clinical range, mechanisms remain still unclear. In this fMRI-study, 61 healthy participants (31 men) from the higher versus lower range of the non-clinical variation in externalization (31 participants with high externalization) as assessed by the subscales disinhibition and meanness of the Triarchic-Psychopathy-Measure (TriPM) performed a monetary modified Taylor-Aggression-Paradigm (mTAP). This paradigm consisted of a mock competitive-reaction-time-task played against a fictional opponent with preprogrammed win- and lose-trials. In lose-trials, participants were provoked by subtraction of an amount of money between 0 and 90 cents. As a manipulation check, provocation induced a significant rise in behavioral aggression levels linked with an increased activation in the anterior cingulate cortex (ACC). High externalization predicted reduced ACC responses to provocation. However, high externalizing participants did not behave more aggressively than the low externalization group. Additionally, the high externalizing group showed a significantly lower positive affect while no group differences emerged for negative affect. In conclusion, high externalization in the non-clinical range was related to neural alterations in regions involved in affective decision-making as well as to changes in affect but did not lead to higher behavioral aggression levels in response to the mTAP. This is in line with previous findings suggesting that aberrations at multiple levels are essential for developing externalizing disorders
Data on deviance predictability in the assessment of mismatch negativity in patients with schizophrenia
We investigated the MMN at electrode Fz to 12% temporally predictable or unpredictable duration decrement deviant stimuli in 29 healthy controls and 31 schizophrenia patients. With a stimulus onset asynchronicity of 500 ms in the regular predictable condition, a deviant occurred every 4 s while it varied randomly in the unpredictable condition.Here we report detailed data tables and multivariate analysis of variance results (MANOVA) on MMN, P3a and standard ERP data including details on follow-up analyses. An extended figure shows MMN difference curves and averages to standard and deviant stimuli in both experimental conditions and subject groups. Keywords: Cognitive Neuroscience, Neurophysiology, Mismatch Negativit
The effect of cognitive training on evoked potentials in schizophrenia
Electrophysiological indices are sensitive to cognitive dysfunction in schizophrenia but have rarely been used to assess benefits of cognitive remediation. Our aim was to evaluate the effect of specific cognitive training approaches on event-related potentials.
Forty-six patients with schizophrenia underwent either auditory (AUD) or visuo-spatial (VIS) cognitive training or treatment-as-usual (TAU). Cognitive training was computer-assisted and administered for 10 sessions within two weeks. Event-related potentials during an active odd-ball paradigm together with clinical and neuropsychological variables were assessed before and after training and again at a two-month follow-up.
Compared to the TAU group both the AUD and VIS training groups showed decreased P2 latency following training. At follow-up, the P2-latency reduction was stable in the VIS group but the AUD group experienced a relapse. Training resulted in improved digit-span backward among neuropsychological variables. Increased P2 amplitude was related to more positive symptoms and lower social-occupational functioning and longer P2 latency was associated with greater severity of stereotyped thinking.
The more general visuo-spatial training appears to have a longer-lasting effect on P2 latency than the specific auditory training. Alternatively, there may be specific auditory discrimination deficits in schizophrenia requiring more extensive training for a stable change
Mismatch negativity latency and cognitive function in schizophrenia.
BACKGROUND: The Mismatch Negativity (MMN) is an event-related potential (ERP) sensitive to early auditory deviance detection and has been shown to be reduced in schizophrenia patients. Moreover, MMN amplitude reduction to duration deviant tones was found to be related to functional outcomes particularly, to neuropsychological (working memory and verbal domains) and psychosocial measures. While MMN amplitude is thought to be correlated with deficits of early sensory processing, the functional significance of MMN latency remains unclear so far. The present study focused on the investigation of MMN in relation to neuropsychological function in schizophrenia. METHOD: Forty schizophrenia patients and 16 healthy controls underwent a passive oddball paradigm (2400 binaural tones; 88% standards [1 kHz, 80 db, 80 ms], 11% frequency deviants [1.2 kHz], 11% duration deviants [40 ms]) and a neuropsychological test-battery. Patients were assessed with regard to clinical symptoms. RESULTS: Compared to healthy controls schizophrenia patients showed diminished MMN amplitude and shorter MMN latency to both deviants as well as an impaired neuropsychological test performance. Severity of positive symptoms was related to decreased MMN amplitude to duration deviants. Furthermore, enhanced verbal memory performance was associated with prolonged MMN latency to frequency deviants in patients. CONCLUSION: The present study corroborates previous results of a diminished MMN amplitude and its association with positive symptoms in schizophrenia patients. Both, the findings of a shorter latency to duration and frequency deviants and the relationship of the latter with verbal memory in patients, emphasize the relevance of the temporal aspect of early auditory discrimination processing in schizophrenia
Linear associations between MMN latency and patient's verbal memory performance.
<p>Scatterplots of immediate (A) and delayed (B) verbal memory performance score against MMN amplitude to frequency deviants at Fz and FCz, respectively.</p
Grand averages of responses to standard and deviant tones and the resulting difference waveforms.
<p>Top: Frequency deviants in controls (A) and patients (B); bottom: Duration deviants in controls (C) and patients (D).</p
Demographic, clinical and neuropsychological characteristics of schizophrenia patients and healthy controls.
<p>Demographic, clinical and neuropsychological characteristics of schizophrenia patients and healthy controls.</p
28 channel EEG amplitude distributions and comparison of the between-group MMN waveforms.
<p>Scalp electrode maps of MMN to frequency deviant (A, B) and duration deviant tones (D, E) in controls (A, D) and patients (B, E). MMN waveforms of patients and controls to frequency (C) and duration deviant tones (F), both at Fz are shown on the right.</p