Brain Imaging, Cognitive Enhancement and Early Schizophrenia

Schizophrenia is a chronic and highly disabling disorder, making it imperative to apply interventions that alter its deleterious effects as early as possible. Impairments in neurocognition and social cognition, which appear to be linked to impaired structural and functional integrity in key brain regions, are the strongest predictors of functional disability in early course schizophrenia,making them key targets for early intervention. Although pharmacologic treatment of cognitive impairments is currently limited,our studies and others, including meta-analyses have shown that cognitive rehabilitation can be effective for addressing cognitive impairment in chronic patients. Most notably, Cognitive Enhancement Therapy (CET), a unique integrated approach to the rehabilitation of social and non-social cognitive impairments developed and tested by Hogarty and colleagues in our group, has shown substantial and lasting effects in chronic schizophrenia patients. Recently, the investigators have shown that the beneficial effects of CET can be successfully extended to those in the early phase of the disorder, resulting in large functional improvements.

The investigators have posited that CET can be particularly effective as an early intervention strategy by capitalizing on a fronto-temporal plasticity reserve, and the investigators are now observing compelling, albeit preliminary evidence that CET can indeed slow the progression of gray matter loss in these very regions of the brain, which is associated with significantly improved cognition (see Preliminary Studies). Preserved structural integrity and improved brain function in fronto-temporal regions may be the critical mechanisms for supporting cognitive improvement in early course schizophrenia, yet remarkably little is known about the neurobiologic effects of cognitive rehabilitation, the durability of these effects post-treatment, and whether an initial fronto-temporal reserve portends a greater treatment response. Our exciting preliminary findings of the neuroprotective effects of CET represent the first study to demonstrate that the structural integrity of the brain in the early course of schizophrenia can be altered using cognitive rehabilitation. It is critical that these morphologic findings are examined with more advanced imaging techniques in larger samples to gain a precise understanding of the underlying neurobiologic mechanisms and predictors of cognitive and functional enhancement in early course schizophrenia. These goals are reflective of the strategic plan of NIMH to identify underlying neural mechanisms of mental disorders that can facilitate treatment, and personalize care to optimize treatment response. To accomplish this, the investigators propose to use comprehensive structural and functional imaging methods to study 102 new early course schizophrenia patients treated for 18 months in a randomized trial of CET or Enriched Supportive Therapy (EST) and: Aim #1: Confirm the neuroprotective effects of CET on fronto-temporal brain structure. Structural magnetic resonance imaging (MRI) assessments will be collected along with cognitive and functional outcome data at baseline, 9, and 18 months. It is hypothesized that patients treated with CET will demonstrate decreased loss of fronto-temporal gray matter relative to EST, and that this neuroprotection will be a mechanism of cognitive and functional improvement. Effects on other key brain regions will also be explored; Aim #2: Examine the effects of CET on fronto-temporal brain function. Functional MRI data using established executive and social cognition paradigms will be collected at baseline, 9, and 18 months along with cognitive and functional outcome data. It is hypothesized that CET patients will demonstrate enhanced fronto-temporal brain activity during these tasks relative to EST (see Section 3C.6.2 for specific predictions), and that this enhanced brain activity will be a mechanism of cognitive and functional improvement. Changes in fronto-temporal functional connectivity and their relations with improved brain structure and cognition will also be explored; and Aim #3: Examine the durability of CET effects on fronto-temporal brain structure and function, cognition, and functional outcome at 1 year post-treatment. Identical neuroimaging, cognitive, and behavioral data will be collected as those assessed during active treatment. It is hypothesized that the differential neurobiologic benefits of CET relative to EST observed in Aims 1 and 2, and the cognitive and functional benefits of CET observed during active treatment will be sustained 1 year post-treatment.

Exploratory Aim: Explore the effects of a fronto-temporal structural and functional reserve on CET treatment response. Moderator analyses will examine whether pre-treatment fronto-temporal structural and functional brain reserves (operationalized in Section 3C.8.2) predict larger cognitive and functional gains in CET. Exploratory analyses will also examine the degree to which later (18 mo) treatment improvement is dependent upon early (9 mo) neuroprotection and increased brain function, which may reflect plasticity.