Sonia Dollfus

Prof. Sonia Dollfus


Research Focus & Metrics

Academic Career Length

27Years (2000-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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12 November 2015 in Schizophrenia Bulletin
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Journal Article
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SDSonia Dollfus
Sonia Dollfus
CMCyril Mach
Cyril Mach
RMRémy Morello
Rémy Morello
Many patients with schizophrenia have negative symptoms, but their evaluation is a challenge. Thus, standardized assessments are needed to facilitate identification of these symptoms. Many tools have been developed, but most are based on observer ratings. Self-evaluation can provide an additional outcome measure and allow patients to be more engaged in their treatment. The aim of this study was to present a novel tool, Self-evaluation of Negative Symptoms (SNS), and demonstrate its validity. Forty-nine patients with schizophrenia and schizoaffective disorders according to DSM-5 were evaluated. Cronbach’s coefficient (α = 0.867) showed good internal consistency. Factor analysis extracted 2 factors (apathy and emotional) that accounted for 75.2% of the variance. The SNS significantly correlated with the Scale of Assessment of Negative Symptoms (r = 0.628) and the Clinician Global Impression on the severity of negative symptoms (r = 0.599), supporting good convergent validity. SNS scores did not correlate with level of insight (r = 0.008), Parkinsonism (r = 0.175) or Brief Psychiatric Rating Scale positive subscores (r = 0.253), which indicates good discriminant validity. The intrasubject reliability of the SNS revealed excellent intraclass correlation coefficients (ICC = 0.942). Taken together, the results show that the SNS has good psychometric properties and satisfactory acceptance by patients. The study also demonstrates the ability of patients with schizophrenia to accurately report their own experiences. Self-assessments of negative symptoms should be more widely employed in clinical practice because they may allow patients with schizophrenia to develop appropriate coping strategies.

1 May 2005 in Biological Psychiatry
Verified
Journal Article
Closed access
SDSonia Dollfus
Sonia Dollfus
ARAnnick Razafimandimby
Annick Razafimandimby
PDPascal Delamillieure
Pascal Delamillieure
PBPerrine Brazo
Perrine Brazo
MJMarc Joliot
Marc Joliot
NTNathalie Tzourio-Mazoyer
Nathalie Tzourio-Mazoyer

1 May 2002 in European Psychiatry
Verified
Journal Article
Closed access
PBP. Brazo
P. Brazo
RMR.M. Marié
R.M. Marié
IHI. Halbecq
I. Halbecq
KBK. Benali
K. Benali
LSL. Segard
L. Segard
SDSonia Dollfus
Sonia Dollfus
Summary: Aim: Because of the heterogeneity of schizophrenia, this study researched different cognitive patterns in distinct subtypes of schizophrenic patients.Methods: Thirty-five Diagnostic and Statistical Manual IV (DSM IV) schizophrenic patients and 35 healthy controls were included. Patients were categorized into deficit, disorganized and positive subtypes with the schedule for the deficit syndrome (SDS) and the positive and negative syndrome scale (PANSS). Executive/attentional functions were assessed with the modified card sorting test (MCST), a test of verbal fluency, the trail making test (TMT) and the Stroop color-word test (Stroop test). Episodic memory was explored through the California verbal learning test (CVLT).Results: The positive subtype had some executive/attentional (fluency and Stroop tests) and mnesic performances in the normal range, suggesting the preservation of good cognitive skills. In contrast, the deficit and disorganized subtypes had major mnesic and executive/attentional dysfunctions compared to healthy subjects. The deficit subtype compared to the control group performed predominantly worse on the MCST and fluency, whereas the disorganized subtype had the lowest scores on the TMT and the Stroop test.Conclusion: This study showed distinct cognitive patterns in deficit, disorganized and positive patients in comparison with the controls, suggesting a heterogeneous cognitive dysfunction in schizophrenia.

18 June 2015 in Schizophrenia Bulletin
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Journal Article
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SDSonia Dollfus
Sonia Dollfus
LLLaurent Lecardeur
Laurent Lecardeur
RMRémy Morello
Rémy Morello
OEOlivier Etard
Olivier Etard
Several meta-analyses have assessed the response of patients with schizophrenia with auditory verbal hallucinations (AVH) to treatment with repetitive transcranial magnetic stimulation (rTMS); however, the placebo response has never been explored. Typically observed in a therapeutic trial, the placebo effect may have a major influence on the effectiveness of rTMS. The purpose of this meta-analysis is to evaluate the magnitude of the placebo effect observed in controlled studies of rTMS treatment of AVH, and to determine factors that can impact the magnitude of this placebo effect, such as study design considerations and the type of sham used.

1 August 2017 in Schizophrenia Research
Verified
Journal Article
Closed access
SDSonia Dollfus
Sonia Dollfus
JLJohn Lyne
John Lyne

28 September 2017 in Schizophrenia Bulletin
Verified
Journal Article
Open access
PDF file
SDSonia Dollfus
Sonia Dollfus
NJNemat Jaafari
Nemat Jaafari
OGOlivier Guillin
Olivier Guillin
BTBenoit Trojak
Benoit Trojak
MPMarion Plaze
Marion Plaze
OEOlivier Etard
Olivier Etard
Introduction: Despite extensive testing, the efficacy of low-frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) of temporo-parietal targets for the treatment of auditory verbal hallucinations (AVH) in patients with schizophrenia is still controversial, but promising results have been reported with both high-frequency and neuronavigated rTMS. Here, we report a double-blind sham-controlled study to assess the efficacy of high-frequency (20 Hz) rTMS applied over a precise anatomical site in the left temporal region using neuronavigation. Methods: Fifty-nine of 74 randomized patients with schizophrenia or schizoaffective disorders (DSM-IV R) were treated with rTMS or sham treatment and fully evaluated over 4 weeks. The rTMS target was determined by morphological MRI at the crossing between the projection of the ascending branch of the left lateral sulcus and the superior temporal sulcus (STS). Results: The primary outcome was response to treatment, defined as a 30% decrease of the Auditory Hallucinations Rating Scale (AHRS) frequency item, observed at 2 successive evaluations. While there was no difference in primary outcome between the treatment groups, the percentages of patients showing a decrease of more than 30% of AHRS score (secondary outcome) did differ between the active (34.6%) and sham groups (9.1%) (P = .016) at day 14. Discussion: This controlled study reports negative results on the primary outcome but demonstrates a transient effect of 20 Hz rTMS guided by neuronavigation and targeted on an accurate anatomical site for the treatment of AVHs in schizophrenia patients.