One of the symptoms seen in patients with schizophrenia and bipolar disorder is disordered thinking. Co-lead authors Junghyup Suh and NARSAD Grantee, David J. Foster, Ph.D., 2013 Foundation Freedman Prize Honorable Mention, have identified a mechanism underlying impaired information processing that may contribute to the cognitive impairments in schizophrenia in a paper published in Neuron on October 16th.

The cognitive symptoms of schizophrenia are thought to result from impairments of information processing in neural circuits. In this new study, the researchers recorded neural activity in the hippocampus of mice with an alteration in the protein calcineurin. Previous studies in the laboratory of Nobel Laureate Susumu Tonegawa at the Massachusetts Institute of Technology suggest that changes in the protein calcineurin slightly increase the risk for developing schizophrenia (a finding extended to bipolar disorder by other researchers).

Previous studies have also shown that hippocampal neurons “replay” activity related to previous events during rest (for example, mice “replay” a maze-running experience after they are finished). This processing post-experience has been implicated in learning, working memory and subsequent memory consolidation. In this study, the researchers found that the brain cells of mice with altered calcineurin don't replay the maze memory in the same way.  

In an editorial accompanying the article in Neuron, Foundation Scientific Council member Patricio O'Donnell, M.D., Ph.D., of Pfizer Pharmaceuticals notes that this observed learning deficit in mice lacking calcineurin establishes a link between neural activity anomalies and cognitive deficits observed in this model of schizophrenia.

Read a summary of this research.