Schizophrenia Spectrum Disorders Show Reduced Specificity and Less Positive Events in Mental Time Travel

Area of Science:

• Cognitive Neuroscience
• Psychiatry
• Mental Health Research

Background:

• Mental time travel, encompassing past recall and future imagination, is crucial for human cognition.
• Schizophrenia (SCZ) is associated with deficits in episodic memory and future thinking.
• Schizotypal personality disorder (SPD) proneness represents a risk factor for developing SCZ, suggesting potential shared cognitive impairments.

Purpose of the Study:

• To investigate episodic past and future thinking abilities in individuals diagnosed with schizophrenia (SCZ).
• To examine mental time travel in individuals with schizotypal personality disorder (SPD) proneness, a population at risk for SCZ.
• To compare these abilities between SCZ patients, SPD proneness individuals, and healthy controls.

Main Methods:

• Utilized the Sentence Completion for Events from the Past Test (SCEPT) and a future events version.
• Assessed past and future thinking specificity and event extension in 32 SCZ patients, 30 SPD proneness individuals, and 33 healthy controls.
• Analyzed the proportion of specific, extended, and positive events generated by each group.

Main Results:

• SCZ patients demonstrated significantly reduced specificity in recalling past and imagining future events compared to controls.
• Individuals with SPD proneness showed reduced event extension compared to healthy controls, with specificity deficits mainly in future thinking.
• Both SCZ patients and SPD proneness individuals generated fewer positive events than controls.

Conclusions:

• Mental time travel, particularly future thinking specificity, is impaired across the schizophrenia (SCZ) spectrum, including in individuals with schizotypal personality disorder (SPD) proneness.
• These findings highlight shared cognitive deficits in episodic memory and future simulation in SCZ spectrum disorders.
• The results have implications for understanding the broader cognitive and emotional impairments observed in these conditions.