Article

Symptomatic and functional correlates of regional brain physiology during working memory processing in patients with recent onset schizophrenia.

Department of Psychology, University of California Los Angeles, Los Angeles, CA 90095, United States.
Psychiatry Research (Impact Factor: 2.68). 09/2009; 173(3):177-82. DOI: 10.1016/j.pscychresns.2009.02.008
Source: PubMed

ABSTRACT Patients with schizophrenia show altered patterns of functional activation during working memory processing; specifically, high-performing patients appear to hyper-activate and low-performing patients appear to hypo-activate when compared with controls. It remains unclear how these individual differences in neurophysiological activation relate to the clinical presentation of the syndrome. In this functional magnetic resonance imaging (fMRI) study, the relationship is examined using partial least squares (PLS), a multivariate statistical technique that selects underlying latent variables based on the covariance between two sets of variables, in this case, clinical variables and regional fMRI activations during a verbal working memory task. The PLS analysis extracted two latent variables, and the significance of these associations was confirmed through permutation. Lower levels of activation during task performance across frontal and parietal regions of interest in the left hemisphere were found to covary with poorer role functioning and greater severity of negative and disorganized symptoms, while lower activation in right frontal and subcortical regions of interest was found to covary with better social functioning and fewer positive symptoms. These results suggest that appropriately lateralized patterns of functional activation during working memory processing are related to the severity of negative and disorganized symptoms and to the level of role and social functioning in schizophrenia.

1 Bookmark
 · 
119 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background and Aim: Schizophrenia is a severe mental illness encompassing a spectrum of cognitive, social, and emotional impairments. One of the serious problems in schizophrenia is functional dysfunction. Emotional face recognition is an effective component of social functioning. The purpose of this study was to examine the relationship between negative emotional faces perception and global function in patients with schizophrenia. Materials and Methods: The method of this study was analytical- descriptive. Using convenience sampling method 30 patients with schizophrenia (16 male/14female, 20-45 years old) were selected from Roozbeh Psychiatric Hospitalof Tehran University of Medical Science (TUMS) in Tehran, Iran. Their functionswere assessed by Global Assessment of Functioning (GAF), and responses to emotional face perception(N170) were recorded by Event Related Potential(ERP). Data were analyzed using Pearson correlation test and linear regression in SPSS software version 15. Results: Results showed that the mean amplitudes of N170 responses to fearful and angry faces in patients with schizophrenia were significantly correlated with the GAFscores (P<0.001). Besides, the amplitudes of N170 responses to angry faces (as compared to fearful faces) could predicate the % 26 of the GAF scores changes by stepwise regression analysis. Conclusion Findings suggested that the functional dysfunction in patients with schizophrenia is due to the deficit in the early stage of facial expression perception. Key words: Schizophrenia, Emotional Face, Global Functioning, N170, ERP
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: LPFC dysfunction is a well-established neural impairment in schizophrenia and is associated with worse symptoms. However, how LPFC activation influences symptoms is unclear. Previous findings in healthy individuals demonstrate that lateral prefrontal cortex (LPFC) activation during cognitive control of emotional information predicts mood and behavior in response to interpersonal conflict, thus impairments in these processes may contribute to symptom exacerbation in schizophrenia. We investigated whether schizophrenia participants show LPFC deficits during cognitive control of emotional information, and whether these LPFC deficits prospectively predict changes in mood and symptoms following real-world interpersonal conflict. During fMRI, 23 individuals with schizophrenia or schizoaffective disorder and 24 healthy controls completed the Multi-Source Interference Task superimposed on neutral and negative pictures. Afterwards, schizophrenia participants completed a 21-day online daily-diary in which they rated the extent to which they experienced mood and schizophrenia-spectrum symptoms, as well as the occurrence and response to interpersonal conflict. Schizophrenia participants had lower dorsal LPFC activity (BA9) during cognitive control of task-irrelevant negative emotional information. Within schizophrenia participants, DLPFC activity during cognitive control of emotional information predicted changes in positive and negative moods on days following highly distressing interpersonal conflicts. Results have implications for understanding the specific role of LPFC in response to social stress in schizophrenia, and suggest that treatments targeting LPFC-mediated cognitive control of emotion could promote adaptive response to social stress in schizophrenia.
    01/2014; 6. DOI:10.1016/j.nicl.2014.08.012
  • [Show abstract] [Hide abstract]
    ABSTRACT: We investigated whether intensive computerized cognitive training in schizophrenia could improve working memory performance and increase signal efficiency of associated middle frontal gyri (MFG) circuits in a functionally meaningful manner. Thirty schizophrenia participants and 13 healthy comparison participants underwent fMRI scanning during a letter N-back working memory task. Schizophrenia participants were then randomly assigned to either 80hours (16weeks) of cognitive training or a computer games control condition. After this intervention, participants completed a second fMRI N-back scanning session. At baseline, during 2-back working memory trials, healthy participants showed the largest and most significant activation in bilateral MFG, which correlated with task performance. Schizophrenia participants showed impaired working memory, hypoactivation in left MFG, and no correlation between bilateral MFG signal and task performance. After training, schizophrenia participants improved their 2-back working memory performance and showed increased activation in left MFG. They also demonstrated a significant association between enhanced task performance and right MFG signal, similar to healthy participants. Both task performance and brain activity in right MFG after training predicted better generalized working memory at 6-month follow-up. Furthermore, task performance and brain activity within bilateral MFG predicted better occupational functioning at 6-month follow-up. No such findings were observed in the computer games control participants. Working memory impairments in schizophrenia and its underlying neural correlates in MFG can be improved by intensive computerized cognitive training; these improvements generalize beyond the trained task and are associated with enduring effects on cognition and functioning 6months after the intervention.
    NeuroImage 05/2014; 99. DOI:10.1016/j.neuroimage.2014.05.057 · 6.13 Impact Factor

Full-text (2 Sources)

Download
21 Downloads
Available from
Jun 2, 2014