Working memory and multidimensional schizotypy: Dissociable influences of the different dimensions

Abstract

Compromised working memory is considered a core deficit of schizophrenia and a potential endophenotype for the liability to develop schizophrenia. In keeping with this suggestion, working memory has also been found to be disrupted in people with high levels of schizotypy. However, it is unclear whether this disruption is linked to positive, negative, or disorganized symptoms/characteristics. This issue is the focus of the present investigation. The relationship between multidimensional schizotypy and working memory performance was investigated in 289 participants. Working memory was measured using an n-back task with three conditions; 0-back, 1-back, and 2-back. Covarying for the effect of shared variance between the schizotypy dimensions, we found reduced working memory performance in participants who displayed high levels of positive schizotypy and, to some extent, in participants with low levels of negative schizotypy. The results are discussed in terms of Baddeley's (1986) model of working memory and potential underlying neurological mechanisms.

Keywords:

• Schizophrenia
• Schizotypy
• Working memory
• Intraparticipant variability

Acknowledgments

This work was supported by a studentship from the Danish Research Council to Mia Schmidt-Hansen.

Notes

¹ η_p ² corresponds in interpretation to R ². Values of η_p ² of .01, .06, and .15 constitute a small, medium, and large effect, respectively (Keppel & Wickens, 2004).

² To the best of our knowledge, the construct validity of the cognitive disorganization scale of the O-LIFE has not been independently examined, which may indicate a need for caution when interpreting the null result obtained in this study in terms of the relationship between cognitive disorganization and working memory performance as measured by our n-back task.