Tendency to experience inaccurate beliefs alongside perceptual anomalies constitutes positive schizotypal traits in the general population and shows continuity with the positive symptoms of schizophrenia. It has been hypothesized that the positive symptomatology of schizophrenia, and by extension, the odd beliefs and unusual perceptual experiences in the general population, are associated with specific alterations in memory functions. An imbalance between memory generalization and episodic memory specificity has been proposed on several counts; however, the direction of the imbalance is currently unclear. Here, we evaluated the association between positive schizotypy, and memory alterations related to hippocampal computations in a general population sample enriched for positive schizotypy. We found that memory generalization is attenuated while memory specificity is elevated in participants with more pronounced positive schizotypal traits. Our findings show that people who are prone to irrational beliefs and unusual experiences also show measurable alterations in memory and likely have difficulty grasping the global picture and rather be overpowered by fragments of information.

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Introduction Meta-analyses suggest that patients with schizophrenia show deficit in working memory – both verbal and visual – and are more distractible. Working memory disturbances are even regarded as the central deficit in schizophrenia by some researchers. Theta synchronization (especially over fronto-central areas) is related to cognitive control and executive functioning during working memory encoding and retention. Objectives The main goal of the study was to gain more understanding of the nature of working memory deficit and attentional distractibility in schizophrenia. Methods 35 patients with schizophrenia and 39 matched controls were enrolled in our study. Participants performed a modified Sternberg working memory task that contained salient and non-salient distractor items in the retention period. A high-density 128 channel EEG was recorded during the task. Event-related theta (4-7 Hz) synchronization was analyzed during working memory encoding (learning) and retention (distractor filtering) in a later time window (350-550 ms). Results Patients with schizophrenia showed weaker working memory performance and increased attentional distractibility compared to the control group: patients had significantly lower hit rates (p < 0.0001) and higher distractor-related commission error rates (p < 0.0001). Theta synchronization was modulated by condition (learning < distractor) in both groups but it was modulated by salience only in controls (salient distractor > non-salient distractor, p[patients] = 0.95, p[controls] < 0.001). Conclusions Our results suggest that patients with schizophrenia show diminished cognitive control compared to controls in response to salient distractors. Difficulties in cognitive control allocation may contribute to the behavioral results observed in this study. Disclosure No significant relationships.

Subjects with high levels of attachment anxiety and neuroticism were proposed to be characterized by higher relative right rather than left frontal activity. Since sleep spindles are argued to reflect enhanced offline neuroplasticity, higher spindle activity measured over the right frontal areas relative to the corresponding left frontal ones could index higher attachment anxiety and neuroticism. Our aim was to explore the relationship between the lateralization patterns of frontally dominant slow sleep spindles and questionnaire measures of adult attachment anxiety and neuroticism. Thirty-four healthy subjects (male = 19; Mage = 31.64; SDage = 9.5) were enrolled in our preliminary study. Second night EEG/polysomnography records and questionnaire measures of personality (Zuckerman–Kuhlman Personality Questionnaire) and adult attachment (Relationship Scales Questionnaire) were collected. Frontal slow sleep spindles were measured by the Individual Adjustment Method (IAM), whereas hemispheric asymmetry indexes of spindle occurrence rate, duration, and amplitude were derived as normalized left–right differences (electrode pairs: Fp1–Fp2, F3–F4, and F7–F8). Relative right lateralization of frontolateral and frontopolar slow sleep spindle density and mid-frontal slow spindle duration were associated with attachment anxiety, but spindle lateralization was less closely related to neuroticism. The relationships between frontal slow spindle laterality and attachment anxiety remained statistically significant even after controlling for the effect of neuroticism, whereas attachment avoidance–independence was not correlated with frontal slow spindle lateralization. Right frontal lateralization of slow sleep spindle activity might indicate attachment status in terms of the negative view of the self.