A.P. Burgess

A.T. Walden

Andreasen

Begić

Benignus

Bullmore

Casella

Coutin-Churchman

Dahlhaus

Dawson

Efron

Fenton

Fiecas

Friston

Galderisi

Gross

Harris

John

Johnson

Leocani

Medkour

Nolte

Percival

Salvador

Stam

Stephan

Strelets

T. Medkour

Talih

Uhlhaas

V.B. Strelets

Walden

Medkour, T

Walden, AT

Burgess, AP

Strelets, VB

Spiral - Imperial College Digital Repository

English

Brain connectivity in positive and negative syndrome schizophrenia.

Crossref

Brain connectivity in positive and negative syndrome schizophrenia

If, as is widely believed, schizophrenia is characterized by abnormalities of brain functional connectivity, then it seems reasonable to expect that different subtypes of schizophrenia could be discriminated in the same way. However, evidence for differences in functional connectivity between the subtypes of schizophrenia is largely lacking and, where it exists, it could be accounted for by clinical differences between the patients (e.g. medication) or by the limitations of the measures used. In this study, we measured EEG functional connectivity in unmedicated male patients diagnosed with either positive or negative syndrome schizophrenia and compared them with age and sex matched healthy controls. Using new methodology (Medkour et al., 2009) based on partial coherence, brain connectivity plots were constructed for positive and negative syndrome patients and controls. Reliable differences in the pattern of functional connectivity were found with both syndromes showing not only an absence of some of the connections that were seen in controls but also the presence of connections that the controls did not show. Comparing connectivity graphs using the Hamming distance, the negative-syndrome patients were found to be more distant from the controls than were the positive syndrome patients. Bootstrap distributions of these distances were created which showed a significant difference in the mean distances that was consistent with the observation that negative-syndrome diagnosis is associated with a more severe form of schizophrenia. We conclude that schizophrenia is characterized by widespread changes in functional connectivity with negative syndrome patients showing a more extreme pattern of abnormality than positive syndrome patients

Brain connectivity in positive and negative syndrome schizophrenia.

Abstract

Similar works

Full text

Available Versions

Spiral - Imperial College Digital Repository

Crossref

Aston Publications Explorer