Docstoc

NEURAL CIRCUITRY UNDERLYING IMPAIRED INSIGHT IN SCHIZOPHRENIA

Document Sample
NEURAL CIRCUITRY UNDERLYING IMPAIRED INSIGHT IN SCHIZOPHRENIA Powered By Docstoc
					NEURAL CIRCUITRY UNDERLYING IMPAIRED INSIGHT IN SCHIZOPHRENIA: AN FMRI STUDY

Mark Benton Department of Psychiatry and Behavioral Neuroscience

What is Schizophrenia?


Schizophrenia is a severe and debilitating mental illness (from Greek, meaning “split mind”). People with schizophrenia suffer terrifying symptoms:  hearing voices that others cannot hear  fearing that people are plotting to harm them  hallucinations





Affects approximately 1% of the population.

What is Insight?


Insight refers to several aspects regarding awareness of a mental illness:
   

awareness of the illness itself the social consequences of the illness the need for treatment correct attribution of symptoms to the illness



Schizophrenia patients who lack insight do not believe that their positive symptoms (i.e. delusions, hallucinations) are caused by their illness.

Why study schizophrenia and insight?



Schizophrenia patients who lack insight have poor clinical outcomes. Recent studies point to specific neurocognitive deficits and structural abnormalities associated with poor insight (Shad et al. 2004).

These observations underlie the need to examine regional alterations in brain function, specifically in the prefrontal cortex, in patients with poor insight.

How can you study Insight and Schizophrenia with fMRI?


Use a paradigm designed to provoke self-evaluation using trait adjectives. Schmitz et al. 2004 used this same paradigm in a group of healthy control subjects. However, there have been no published reports using this task in any psychiatric population. Are the brain regions activated during this task the same in schizophrenics and healthy controls? If not, how do they differ? Do we see functional impairments (i.e. reduced activation) in areas of the brain previously implicated in insight impairment, namely the DLPFC?







I am …

Shy
NO

YES

MARK is …

Likeable
NO

YES

Is this word positive ?

Intelligent
NO

YES

Preliminary Findings
SELF vs. WORD OTHER vs. WORD



N=4

SELF vs. OTHER

Future Directions


Evaluating oneself, compared to evaluating a close friend or relative, activates the dorsal lateral prefrontal cortex (DLPFC):


Executive function
• Self-monitoring • Conceptual organization



Working memory



This is an area of the brain shown to have decreased volumes in patients with poor insight (Shad et al. 2004). Now that we have replicated previous findings and shown such a study is feasible, we intend to continue scanning SZ subjects with poor insight.




				
DOCUMENT INFO
Shared By:
Stats:
views:66
posted:7/10/2008
language:English
pages:10