An Integrated Neurophysiological Approach Toward the Early Detection of Psychiatric Disorders

NCT06886945 | Recruiting

• 1 other identifier: PNRR-SCZ-EXP1
• Study Type: observational
• Target: 75
• Locations: 1 country
• Sites: 1

Brief Summary

Schizophrenia (SCZ) is a severe neuropsychiatric disorder characterized by cognitive decline, social withdrawal, and positive symptoms such as hallucinations and delusions. Research suggests that SCZ and schizotypy exist along a continuum, with shared structural and behavioral abnormalities, the latter of which encompass the sensory and perceptual domain, often in the form of altered multisensory integration, as seen in tasks like the Sound-Induced Flash Illusion (SIFI). Individuals with schizotypal traits or SCZ show enlarged temporal binding windows (TBW) of cross-modal integration, affecting perceptual accuracy and multisensory judgments. However, whether these deficits stem from overactive top-down modulation or weakened bottom-up sensory precision remains unclear. The current study seeks to address these questions, by asking participants (healthy individuals screened as for their schizotypal traits, and patients suffering from SCZ) to complete a modified version of the SIFI, as well as an audiovisual temporal order judgment (TOJ) task. Cross-modal performance will be assessed via signal detection theory (SDT) metrics and psychometric modeling to estimate individual TBWs, thereby assaying audiovisual processing abilities along the schizotypal continuum

Conditions

Schizophrenia Disorders

Keywords

Schizophrenia; Audio-Visual Integration; Temporal Binding Windows; Signal Detection Theory; Schizotypal Personality

Outcome Measures

Primary Outcomes (1)

• Temporal Binding Window (TBW) length

  The temporal binding window (TBW) is a psychophysical construct that reflects an observer's tolerance for temporal asynchrony-a "window" of time within which multisensory stimuli are likely to be perceptually bound or integrated. As such, it serves as a proxy for cross-modal performance. In both tasks, individual TBWs will be estimated for each participant by fitting gaussian and sigmoidal logistic functions to error rates (i.e., inverse accuracy) and perceptual sensitivity metrics (i.e., d', as computed combining hits and flase alarms according to signal detection theory), respectively, across the asynchrony space (e.g., at each SOA). The width (e.g., standard deviation) of the gaussian function and the inflection point (e.g., midpoint) of the sigmoidal curve will be then derived on a participant-by-participant basis, serving as behavioral indices of TBW span (in milliseconds) for further statistical analyses and comparison between groups.

  Right after tasks completion

Study Arms (3)

SCZ

Patients diagnosed with schizophrenia spectrum disorders

Other: Audio-Visual Perceptual Tasks

LST

Healthy individuals displaying low schizotypal traits

Other: Audio-Visual Perceptual Tasks

HST

Healthy individuals displaying high schizotypal traits

Other: Audio-Visual Perceptual Tasks

Interventions

Audio-Visual Perceptual Tasks OTHER

Around 75 participants will be recruited for this study (25 per each group), and asked to perform two distinct audiovisual tasks (run via Matlab-based automated routines, and presented using a CRT monitor and a pair of loudspeakers) : 1. TOJ task, in which a white flashing dot, and a basic auditory stimulus, will be presented in close temporal proximity at several stimulus onset asynchronies (SOAs, from 30 to 540 ms in steps of 30 ms), with participants asked to report ( after each trial), which stimulus occurred first (task duration estimate: 25 minutes, 30 trials per each SOA) 2. A modified version of the SIFI (mSIFI), in which the presentation of paired (and temporally close) auditory stimuli will be coupled with the occurrence of either 1 or 2 flashing dots, at several different SOAs (from 30 to 250 ms in steps of 10 ms), with participants asked to report (after each trial), whether they saw 1 vs 2 flashes (task duration estimate: 25 minutes, 30 trials per each SOA)

HST; LST; SCZ

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Probability Sample

Study Population

Healthy participants assigned either to the low (LST) or high (HST) schizotypal group will be recruited from the general population, after being screened for their schizotypal traits via the Schizotypal Personality Questionnaire (SPQ, Raine, 1991). Individuals with SPQ scores falling within the first and last quintile of the overall SPQ scores distribution will then be recruited and assigned, respectively, to the LST and HST groups. SCZ patients will be recruited via the Psychiatric Unit of IRCCS Centro San Giovanni di Dio Fatebenefratelli

You may qualify if:

• Normal hearing
• Normal or corrected-to-normal vision
• Clinical diagnosis of schizophrenia spectrum disorder (according to DSM-5)
• IQ \> 70

You may not qualify if:

• Anamnesis or evidence of any central nervous system alteration
• Current major physical illness
• Drug dependency/abuse over the last 6 months
• Unstable pharmacological therapy
• Comorbidities with other major psychiatric disorders

Sponsors & Collaborators

• IRCCS Centro San Giovanni di Dio Fatebenefratelli: lead
• University of Bologna: collaborator

Study Sites (1)

IRCCS Centro San Giovanni di Dio Fatebenefratelli

Brescia, BS, 24125, Italy

RECRUITING

MeSH Terms

Conditions

Schizophrenia; Schizotypal Personality Disorder

Condition Hierarchy (Ancestors)

Schizophrenia Spectrum and Other Psychotic Disorders; Mental Disorders; Personality Disorders

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 14, 2025
• First Posted: March 20, 2025
• Study Start: April 9, 2024
• Primary Completion: October 1, 2025
• Study Completion: October 1, 2025
• Last Updated: March 20, 2025

Record last verified: 2025-03

Locations

IT (1)