Impaired contour object perception in psychosis.

Area of Science:

• Neuroscience
• Cognitive Psychology
• Psychiatry

Background:

• Contour integration, the ability to perceive unified lines from disparate elements, is known to be impaired in schizophrenia.
• Emerging evidence suggests this deficit may be linked to broader psychotic symptoms rather than specific diagnoses.

Purpose of the Study:

• To investigate contour integration deficits in a transdiagnostic sample of individuals with psychotic psychopathology (PwPP).
• To explore the neural underpinnings of these deficits using functional MRI and connectivity analyses.

Main Methods:

• A psychophysical behavioral task was used to quantify contour discrimination performance in PwPP, healthy controls, and relatives of PwPP.
• Ultra-high field (7T) functional MRI measured brain activity and functional connectivity during an analogous contour perception task.

Main Results:

• PwPP demonstrated significantly impaired contour discrimination compared to controls and their relatives.
• Individuals with schizophrenia performed worse than those with bipolar disorder on the task.
• PwPP showed heightened activity in the lateral occipital cortex and abnormal visual functional connectivity, especially when distinguishing targets from distractors.

Conclusions:

• Contour integration is impaired across psychotic psychopathology, with particular deficits observed in schizophrenia.
• These visual processing impairments are associated with cognitive dysfunction and aberrant functional connectivity within visual brain networks.
• A failure to effectively suppress background noise may contribute to the observed contour processing difficulties in PwPP.