Université de Fribourg

Disruption of gamma–delta relationship related to working memory deficits in first-episode psychosis

Missonnier, Pascal ; Prévot, Anne ; Herrmann, François R. ; Ventura, Joseph ; Padée, Anna ; Merlo, Marco C. G.

In: Journal of Neural Transmission, 2020, vol. 127, no. 1, p. 103–115

Working memory (WM) deficits constitute a core symptom of schizophrenia. Inadequacy of WM maintenance in schizophrenia has been reported to reflect abnormalities in the excitation/inhibition (E/I) balance between pyramidal neurons and parvalbumin basket cells, which may explain alterations of the dynamics of gamma and delta oscillations. To address this issue, we assessed event-related gamma...

Université de Fribourg

Impaired social cognition in schizophrenia during the Ultimatum Game: An EEG study

Horat, Sibylle K. ; Favre, Grégoire ; Prévot, Anne ; Ventura, Joseph ; Herrmann, François R. ; Gothuey, Isabelle ; Merlo, Marco C.G. ; Missonnier, Pascal

In: Schizophrenia Research, 2018, vol. 192, p. 308–316

Schizophrenia has a core feature of cognitive dysfunctions. Since these deficits are predictive for patients' functional outcome, understanding their origin is of great importance to improve their daily lives. A specific component of the deficit involves social decision-making, which can be studied using the Ultimatum Game (UG). In this task, a “proposer” proposes a share of money to a...

Université de Fribourg

Differences of temporal dynamics and signal complexity of gamma band oscillations in first-episode psychosis during a working memory task

Missonnier, Pascal ; Curtis, Logos ; Ventura, Joseph ; Herrmann, François R. ; Merlo, Marco C. G.

In: Journal of Neural Transmission, 2017, vol. 124, no. 7, p. 853–862

Gamma band oscillations participate in the temporal binding needed to synchronize cortical networks, involved in early sensory and short term memory processes. In earlier studies, alterations of these neurophysiological parameters have been found in psychotic disorders. To date no study has explored the temporal dynamics and signal complexity of gamma band oscillations in first episode psychosis...

Université de Fribourg

Differences in social decision-making between proposers and responders during the ultimatum game: an eeg study

Horat, Sibylle K. ; Prévot, Anne ; Richiardi, Jonas ; Herrmann, François R. ; Favre, Grégoire ; Merlo, Marco C. G. ; Missonnier, Pascal

In: Frontiers in Integrative Neuroscience, 2017, vol. 11, p. -

The Ultimatum Game (UG) is a typical paradigm to investigate social decision-making. Although the behavior of humans in this task is already well established, the underlying brain processes remain poorly understood. Previous investigations using event-related potentials (ERPs) revealed three major components related to cognitive processes in participants engaged in the responder condition, the...

Université de Fribourg

Assessment of mental workload: A new electrophysiological method based on intra-block averaging of ERP amplitudes

Horat, Sibylle K. ; Herrmann, François R. ; Favre, Grégoire ; Terzis, Jorge ; Debatisse, Damien ; Merlo, Marco C.G. ; Missonnier, Pascal

In: Neuropsychologia, 2016, vol. 82, p. 11–17

The present study contributes to the current debate about electrophysiological measurements of mental workload. Specifically, the allocation of attentional resources during different complexity levels of tasks and its changes over time are of great interest. Therefore, we investigated mental workload using tasks varying in difficulty during an auditory oddball target paradigm. For data...

Université de Fribourg

The Brief Psychiatric Rating Scale (version 4.0) factorial structure and its sensitivity in the treatment of outpatients with unipolar depression

Zanello, Adriano ; Berthoud, Laurent ; Ventura, Joseph ; Merlo, Marco C.G.

In: Psychiatry Research, 2013, vol. 210, no. 2, p. 626–633

The 24-item Brief Psychiatric Rating Scale (BPRS, version4.0) enables the rater to measure psychopathology severity. Still, little is known about the BPRS's reliability and validity outside of the psychosis spectrum. The aim of this study was to examine the factorial structure and sensitivity to change of the BPRS in patients with unipolar depression. Two hundred and forty outpatients with...