Florence Hagenmuller

The ZInEP Epidemiology Survey: background, design and methods.

This article introduces the design, sampling, field procedures and instruments used in the ZInEP Epidemiology Survey. This survey is one of six ZInEP projects (Zürcher Impulsprogramm zur nachhaltigen Entwicklung der Psychiatrie, i.e. the “Zurich Program for Sustainable Development of Mental Health Services”). It parallels the longitudinal Zurich Study with a sample comparable in age and gender, and with similar methodology, including identical instruments. Thus, it is aimed at assessing the change of prevalence rates of common mental disorders and the use of professional help and psychiatric sevices. Moreover, the current survey widens the spectrum of topics by including sociopsychiatric questionnaires on stigma, stress related biological measures such as load and cortisol levels, electroencephalographic (EEG) and near‐infrared spectroscopy (NIRS) examinations with various paradigms, and sociophysiological tests. The structure of the ZInEP Epidemiology Survey entails four subprojects: a short telephone screening using the SCL‐27 (n of nearly 10,000), a comprehensive face‐to‐face interview based on the SPIKE (Structured Psychopathological Interview and Rating of the Social Consequences for Epidemiology: the main instrument of the Zurich Study) with a stratified sample (n = 1500), tests in the Center for Neurophysiology and Sociophysiology (n = 227), and a prospective study with up to three follow‐up interviews and further measures (n = 157). In sum, the four subprojects of the ZInEP Epidemiology Survey deliver a large interdisciplinary database. Copyright

Determination of the loudness dependence of auditory evoked potentials: single‐electrode estimation versus dipole source analysis

The loudness dependence of auditory evoked potentials (LDAEP) has been described as a measure of central serotonergic activity. Single‐electrode estimation and dipole source analysis (DSA) are the most utilized methods for the estimation of LDAEP. To date, it is assumed that both methods are equally reliable. Nevertheless, according to our knowledge, the advantage of either method has not yet been shown directly. The aim of our study was to compare single‐electrode estimation and dipole source analysis in the determination of the LDAEP.

Empathische Resonanzfähigkeit bei Straftätern mit psychopathischen Persönlichkeitszügen

SummaryBackgroundResonance is the phenomenon of unconsciously mirroring the motor actions of another person. Beside autism and schizophrenia psychopathic personality traits are associated with empathy dysfunction.MethodsWe explore empathic resonance in terms of contagion by laughing and yawning in a group of offenders with psychopathic traits. Offenders with psychopathic traits (n = 12) and matched controls (n = 10) were video-taped while watching short video sequences of yawning, laughing or neutral faces. They were rated regarding contagion. Further, we assessed a self-report on psychopathy and on empathic tendencies.ResultsCompared to the control group, the offenders showed significantly less contagion and less self-reported empathic tendencies. Individuals who rated themselves as more empathic showed more contagion.ConclusionsThe observed reduced resonance in terms of contagion may illuminate the cold-heartedness, with which some psychopathic offenders treat their victims: When embodied experiencing of other’s physical and emotional situation is missing, a natural inhibition of violence may be overcome. The small sample size limits the generalisability of these findings.ZusammenfasssungGrundlagenResonanz ist das unbewusste körpernahe Miterleben eines motorischen, vegetativen oder emotionalen Zustands einer anderen Person und stellt eine wichtige Grundlage der Empathie dar. Neben Autismus und Schizophrenie werden auch die psychopathischen Persönlichkeitszüge mit Empathiedysfunktionen assoziiert.MethodikIn der vorliegenden Studie wird die empathische Resonanzfähigkeit im Sinne von Ansteckung durch Lachen und Gähnen bei Straftätern mit psychopathischen Persönlichkeitszügen untersucht. Während sie kurze Videosequenzen mit lachenden, gähnenden und neutralen Gesichtern anschauten, wurden Straftäter (n = 12) und Kontrollprobanden (n = 10) auf Video aufgezeichnet und hinsichtlich der zu beobachtenden Ansteckung eingeschätzt. Zusätzlich wurden die Selbsteinschätzung psychopathischer Züge und empathischer Fähigkeiten erhoben.ErgebnisseIm Vergleich zur Kontrollgruppe zeigte die Straftätergruppe signifikant weniger Ansteckung und weniger selbst-eingeschätzte empathische Fähigkeiten. Probanden, die sich als empathischer einschätzen, zeigten mehr Ansteckung.SchlussfolgerungenDie beobachtete reduzierte Resonanz im Sinne von Ansteckung könnte die Kaltherzigkeit mancher psychopathischer Straftäter erklären: eine reduzierte körperbezogene Nachempfindung physischer und emotionaler Situationen anderer könnte die Überwindung natürlicher Gewalthemmung begünstigen.BACKGROUND Resonance is the phenomenon of unconsciously mirroring the motor actions of another person. Beside autism and schizophrenia psychopathic personality traits are associated with empathy dysfunction. METHODS We explore empathic resonance in terms of contagion by laughing and yawning in a group of offenders with psychopathic traits. Offenders with psychopathic traits (n = 12) and matched controls (n = 10) were video-taped while watching short video sequences of yawning, laughing or neutral faces. They were rated regarding contagion. Further, we assessed a self-report on psychopathy and on empathic tendencies. RESULTS Compared to the control group, the offenders showed significantly less contagion and less self-reported empathic tendencies. Individuals who rated themselves as more empathic showed more contagion. CONCLUSIONS The observed reduced resonance in terms of contagion may illuminate the cold-heartedness, with which some psychopathic offenders treat their victims: When embodied experiencing of others physical and emotional situation is missing, a natural inhibition of violence may be overcome. The small sample size limits the generalisability of these findings.

Early somatosensory processing in individuals at risk for developing psychoses

Human cortical somatosensory evoked potentials (SEPs) allow an accurate investigation of thalamocortical and early cortical processing. SEPs reveal a burst of superimposed early (N20) high-frequency oscillations around 600 Hz. Previous studies reported alterations of SEPs in patients with schizophrenia. This study addresses the question whether those alterations are also observable in populations at risk for developing schizophrenia or bipolar disorders. To our knowledge to date, this is the first study investigating SEPs in a population at risk for developing psychoses. Median nerve SEPs were investigated using multichannel EEG in individuals at risk for developing bipolar disorders (n = 25), individuals with high-risk status (n = 59) and ultra-high-risk status for schizophrenia (n = 73) and a gender and age-matched control group (n = 45). Strengths and latencies of low- and high-frequency components as estimated by dipole source analysis were compared between groups. Low- and high-frequency source activity was reduced in both groups at risk for schizophrenia, in comparison to the group at risk for bipolar disorders. HFO amplitudes were also significant reduced in subjects with high-risk status for schizophrenia compared to healthy controls. These differences were accentuated among cannabis non-users. Reduced N20 source strengths were related to higher positive symptom load. These results suggest that the risk for schizophrenia, in contrast to bipolar disorders, may involve an impairment of early cerebral somatosensory processing. Neurophysiologic alterations in schizophrenia precede the onset of initial psychotic episode and may serve as indicator of vulnerability for developing schizophrenia.

Mismatch negativity: Alterations in adults from the general population who report subclinical psychotic symptoms

BACKGROUND Deficits of mismatch negativity (MMN) in schizophrenia and individuals at risk for psychosis have been replicated many times. Several studies have also demonstrated the occurrence of subclinical psychotic symptoms within the general population. However, none has yet investigated MMN in individuals from the general population who report subclinical psychotic symptoms. METHODS The MMN to duration-, frequency-, and intensity deviants was recorded in 217 nonclinical individuals classified into a control group (n=72) and three subclinical groups: paranoid (n=44), psychotic (n=51), and mixed paranoid-psychotic (n=50). Amplitudes of MMN at frontocentral electrodes were referenced to average. Based on a three-source model of MMN generation, we conducted an MMN source analysis and compared the amplitudes of surface electrodes and sources among groups. RESULTS We found no significant differences in MMN amplitudes of surface electrodes. However, significant differences in MMN generation among the four groups were revealed at the frontal source for duration-deviant stimuli (P=0.01). We also detected a trend-level difference (P=0.05) in MMN activity among those groups for frequency deviants at the frontal source. CONCLUSIONS Individuals from the general population who report psychotic symptoms are a heterogeneous group. However, alterations exist in their frontal MMN activity. This increased activity might be an indicator of more sensitive perception regarding changes in the environment for individuals with subclinical psychotic symptoms.

The Loudness Dependence of Auditory Evoked Potentials (LDAEP) in individuals at risk for developing bipolar disorders and schizophrenia

OBJECTIVES The Loudness Dependence of Auditory Evoked Potentials (LDAEP) is considered as an indicator of central serotonergic activity. Alteration of serotonergic neurotransmission was reported in bipolar disorders and schizophrenia. In line with previous reports on clinically manifest disorders, we expected a weaker LDAEP in subjects at risk for bipolar disorders and schizophrenia compared to healthy controls. METHODS We analyzed LDAEP of individuals at risk for developing bipolar disorders (n=27), with high-risk status (n=74) and ultra-high-risk status for schizophrenia (n=86) and healthy controls (n=47). RESULTS The LDAEP did not differ between subjects at risk for schizophrenia or bipolar disorders and controls. Among subjects without medication (n=122), the at-risk-bipolar group showed a trend towards a weaker LDAEP than both the high-risk and the ultra-high-risk groups for schizophrenia. CONCLUSIONS The LDAEP did not appear as a vulnerability marker for schizophrenia or bipolar disorders. This suggests that an altered LDAEP may not be measurable until the onset of clinically manifest disorder. However, the hypothesis that pathogenic mechanisms leading to bipolar disorders may differ from those leading to schizophrenia is supported. SIGNIFICANCE This is the first study investigating LDAEP in a population at risk for bipolar disorders.

Juicy lemons for measuring basic empathic resonance.

Watch or even think of someone biting into a juicy lemon and your saliva will flow. This is a phenomenon of resonance, best described by the Perception-Action Model, where a physiological state in a person is activated through observation of this state in another. Within a broad framework of empathy, including manifold abilities depending on the Perception-Action link, resonance has been proposed as one physiological substrate for empathy. Using 49 healthy subjects, we developed a standardized salivation paradigm to assess empathic resonance at the autonomic level. Our results showed that this physiological resonance correlated positively with self-reported empathic concern. The salivation test, delivered an objective and continuous measure, was simple to implement in terms of setup and instruction, and could not easily be unintentionally biased or intentionally manipulated by participants. Therefore, these advantages make such a test a useful tool for assessing empathy-related abilities in psychiatric populations.

Distribution of Response Time, Cortical, and Cardiac Correlates during Emotional Interference in Persons with Subclinical Psychotic Symptoms

A psychosis phenotype can be observed below the threshold of clinical detection. The study aimed to investigate whether subclinical psychotic symptoms are associated with deficits in controlling emotional interference, and whether cortical brain and cardiac correlates of these deficits can be detected using functional near-infrared spectroscopy (fNIRS). A data set derived from a community sample was obtained from the Zurich Program for Sustainable Development of Mental Health Services. 174 subjects (mean age 29.67 ± 6.41, 91 females) were assigned to four groups ranging from low to high levels of subclinical psychotic symptoms (derived from the Symptom Checklist-90-R). Emotional interference was assessed using the emotional Stroop task comprising neutral, positive, and negative conditions. Statistical distributional methods based on delta plots [behavioral response time (RT) data] and quantile analysis (fNIRS data) were applied to evaluate the emotional interference effects. Results showed that both interference effects and disorder-specific (i.e., group-specific) effects could be detected, based on behavioral RTs, cortical hemodynamic signals (brain correlates), and heart rate variability (cardiac correlates). Subjects with high compared to low subclinical psychotic symptoms revealed significantly reduced amplitudes in dorsolateral prefrontal cortices (interference effect, p < 0.001) and middle temporal gyrus (disorder-specific group effect, p < 0.001), supported by behavioral and heart rate results. The present findings indicate that distributional analyses methods can support the detection of emotional interference effects in the emotional Stroop. The results suggested that subjects with high subclinical psychosis exhibit enhanced emotional interference effects. Based on these observations, subclinical psychosis may therefore prove to represent a valid extension of the clinical psychosis phenotype.

Determination of the loudness dependence of auditory evoked potentials

The loudness dependence of auditory evoked potentials (LDAEP) has been described as a measure of central serotonergic activity. Single‐electrode estimation and dipole source analysis (DSA) are the most utilized methods for the estimation of LDAEP. To date, it is assumed that both methods are equally reliable. Nevertheless, according to our knowledge, the advantage of either method has not yet been shown directly. The aim of our study was to compare single‐electrode estimation and dipole source analysis in the determination of the LDAEP.

Determination of the loudness dependence of auditory evoked potentials: single-electrode estimation versus dipole source analysis: SINGLE-ELECTRODE METHOD VERSUS DSA IN LDAEP

The loudness dependence of auditory evoked potentials (LDAEP) has been described as a measure of central serotonergic activity. Single‐electrode estimation and dipole source analysis (DSA) are the most utilized methods for the estimation of LDAEP. To date, it is assumed that both methods are equally reliable. Nevertheless, according to our knowledge, the advantage of either method has not yet been shown directly. The aim of our study was to compare single‐electrode estimation and dipole source analysis in the determination of the LDAEP.