A Meta-Analysis of Autobiographical Memory Studies in Schizophrenia Spectrum Disorder

Abstract

Meta-analyses and reviews on cognitive disorders in schizophrenia have shown that the most robust and common cognitive deficits are found in episodic memory and executive functions. More complex memory domains, such as autobiographical memory (AM), are also impaired in schizophrenia, but such impairments are reported less often despite their negative impact on patients' outcome. In contrast to episodic memory, assessed in laboratory tasks, memories of past personal events are much more complex and directly relate to the self. The meta-analysis included 20 studies, 571 patients with schizophrenia spectrum disorder, and 503 comparison subjects. It found moderate-to-large effect sizes with regard to the 3 parameters commonly used to assess AM: memory specificity (g = -0.97), richness of detail (g = -1.40), and conscious recollection (g = -0.62). These effect sizes were in the same range as those found in other memory domains in schizophrenia; for this reason, we propose that defective memories of personal past events should be regarded as a major cognitive impairment in this illness.

Keywords: cognitive remediation; conscious recollection; episodic memory; rehabilitation; self.

Figure 1.

Forest plot of memory specificity for past events

Figure 2.

Forest plot of richness of memory detail for past events

Figure 3.

Forest plot of conscious recollection for past events