Evidence from structural and diffusion tensor imaging for frontotemporal deficits in psychometric schizotypy

Area of Science:

• Neuroimaging
• Psychiatry
• Cognitive Neuroscience

Background:

• Previous research supports a continuum of psychotic symptoms in the general population.
• Few studies have investigated the neural underpinnings of psychometric schizotypy using advanced imaging techniques.

Purpose of the Study:

• To examine the structural and diffusion tensor imaging (DTI) correlates of psychometric schizotypy in healthy adults.
• To compare brain structure and white matter integrity between individuals with high and low schizotypy scores.

Main Methods:

• Healthy volunteers (ages 18-68) completed the Schizotypal Personality Questionnaire.
• Structural MRI and DTI scans were acquired to assess gray/white matter volume, cortical thickness, and fractional anisotropy (FA).
• Comparisons were made between high (N=67) and low (N=71) schizotypy groups in frontal and temporal regions.

Main Results:

• Elevated schizotypy correlated with decreased gray matter volume in frontal and temporal lobes and reduced temporal gray matter thickness.
• Specific reductions were observed in rostral middle frontal cortex and pars orbitalis gray matter volume.
• High schizotypy individuals showed lower FA in the inferior fronto-occipital fasciculus and greater rightward asymmetry in the uncinate fasciculus.

Conclusions:

• Findings align with neurobiological data on psychometric schizotypy, schizotypal personality disorder, and schizophrenia.
• Frontotemporal lobe dysfunction appears to be a key component of the psychosis phenotype.
• This study highlights the utility of neuroimaging in understanding the spectrum of psychosis.