Effects of Cognitive Remediation Therapy on Schizophrenia Patients Through Functional Magnetic Resonance Imaging

Analysis of the Effects of Cognitive Remediation Therapy on Schizophrenia Patients Through fMRI Techniques

Cognitive Remediation Therapy (CRT) can enhance cognitive performance in patients with schizophrenia improving clinical outcome. However, the neurobiological mechanism underlying cognitive improvement is not well understood. The aim of this study is to investigate functional connectivity patterns before and after the neurocognitive rehabilitation therapy, especially in fronto-temporal circuitry.

A controlled randomized study will be carry out with three different groups: patients receiving cognitive rehabilitation treatment (CRT), patients receiving another psychological intervention of control and a healthy control group. A descriptive study of cases will be also carried out. The functional MRI (fRMI) techniques as well as voxel-based morphometry allow individual analysis of cases.

The independent variable is the cognitive rehabilitation treatment. The CRT will be applied according to the manual of Wykes & Reeder (2005) Cognitive Remediation Therapy: Theory and Practice, Ed: Routledge. The program has a duration of 40 sessions (one hour of duration), with two sessions for week during four months. It is carried out individually and utilizes paper and pencil tasks. The main technique utilized is the scaffolding (to provide strategies when the patient cannot carry out the task and to withdraw him when he is yet able of doing it alone) in a context of learning without errors.

The main dependent variable is the functional connectivity cerebral pattern obtained by means of functional magnetic resonance. Other secondary dependent variables are neurocognitive functioning, the symptomatic pattern and the psychosocial functioning obtained from the psychometric evaluation.

All the participants will be evaluated before and after the experimental intervention in neurocognitive areas (Battery will be composed by WAIS-III, RAVLT, Trail Making Test, STROOP color word, WCST, FAS-COWAT), symptomatic area (PANSS) and in social functioning (Social Functioning Scale SFS; Birchwood et al. 1990). The evaluations will be carried out by expert evaluators that will be blind to the experimental distribution. The statistics results analysis will be carry out by means of the statistical package SPSS 15.

Inclusion Criteria:

• Diagnosis of schizophrenia according to DSM-IV-TR and confirmed by the semi-structured interview (SCID) for the axis 1.
• Presence of cognitive deficit confirmed by the neuropsychological battery.
• Stable symptomatology at least during the last six months and the estimation of not modifying pharmacological antipsychotic treatment.

Exclusion Criteria:

• Presence of organic-cerebral affectation due to neurological or traumatic conditions
• Abuse of psychotropic substances
• Presence of other psychiatric symptomatology