Exploring intermediate phenotypes with EEG: Working memory dysfunction in schizophrenia

This review brings together two strands of investigation in the neuropsychology and neurophysiology of schizophrenia that have been particularly productive over the last 20 years. We review the literature on working memory deficits, particularly in the visual domain, and changes in oscillatory neural activity as measured with electroencephalography (EEG) and magnetoencephalography (MEG). We argue that recent results suggest a link between these two phenomena, in that altered oscillations underlie some of the working memory deficits. We furthermore argue that early sensory mechanisms contribute more to working memory (and other) deficits than previously thought. The final part of our review suggests links between working memory, oscillations, and their alterations in schizophrenia and the dopamine, GABA, glutamate and acetylcholine system. These links have already resulted in the development of new remediation strategies, which have some translational potential.

Research highlights▶ Basic sensory deficits during encoding contribute to working memory deficits in patients with schizophrenia. ▶ Abnormalities in synchronous oscillatory underlie some of the working memory deficits in these patients. ▶ There is a link between deficits in working memory, oscillations and the dopamine, GABA, glutamate and acetylcholine system. ▶ These links offer an important line of research for the development of targeted neurochemical and behavioural therapies for cognitive deficits.