Re: Auditory fMRI as a reliable diagnostic of schizophrenia? (Pierre Divenyi )

Subject: Re: Auditory fMRI as a reliable diagnostic of schizophrenia?
From:    Pierre Divenyi  <pdivenyi(at)EBIRE.ORG>
Date:    Fri, 23 Apr 2004 19:20:08 -0700

Interesting. However, the composition of the control group may be
disputable. Should not they have compared their schizophrenic sample with,
say, a manic-depressive sample?

Pierre Divenyi

At 06:54 PM 4/23/2004, Tony Miller wrote:
>[I thought some AUDITORY listmembers might be interested... -AJM]
>
>-----------------Press Release--------------------
>http://www.yale.edu/opa/newsr/04-04-21-01.all.html
>
>Imaging test could be used to diagnose schizophrenia
>
>New Haven, Conn. -- An abnormal pattern in an area of the brain that
>governs hearing may be an accurate method of diagnosing schizophrenia,
>according to a study by Yale researchers and collaborators.
>
>"These results seem to point to a cardinal abnormality in
>schizophrenia," said Godfrey Pearlson, M.D., professor of psychiatry at
>Yale School of Medicine, director of the Olin Neurospychiatry Research
>Center at the Institute of Living in Hartford, and senior author of the
>study published in Biological Psychiatry. "Using this imaging test, we
>were able to identify patients with schizophrenia with 97 percent accuracy."
>
>Pearlson, Vince Calhoun and Kent Kiehl later replicated their initial
>finding with an independent sample and achieved a 94 percent rate of
>accuracy. Calhoun and Kiehl have appointments at the Olin Center and Yale.
>
>Currently, the clinical diagnosis of schizophrenia is based on a
>constellation of psychiatric symptoms. The mental illness also has been
>associated with both structural and functional abnormalities in
>neocortical networks including frontal, parietal, and temporal regions
>of the brain, but there has been no diagnostic test for the disorder.
>
>Abnormalities in auditory cortex structure and function are prominent
>features of the brains in persons with schizophrenia, particularly in
>the superior temporal gyrus (SRG). Reduction in size of the SRG may
>correlate with the severity of auditory hallucinations and of formal
>thought disorder. However, all of these previously documented anatomic
>differences overlap significantly with those of healthy controls and are
>thus not useful for diagnosis.
>
>"Therefore, this newly reported functional brain change results in
>almost total separation of patients and healthy controls in two
>independent samples, and thus has possible diagnostic utility," Pearlson
>said.
>
>Data were collected from two locations. One group consisted of 17
>outpatients with chronic schizophrenia matched with 17 healthy persons
>in Vancouver, B.C. Another group consisted of eight patients and eight
>healthy persons in Hartford, Conn.
>
>"These results have the potential to provide a powerful, quantitative
>clinical tool for the assessment of schizophrenia," Pearlson said.
>
>-----------------Pubmed Abstract--------------------
>
>http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15050866
>
>Aberrant localization of synchronous hemodynamic activity in auditory
>cortex reliably characterizes schizophrenia.
>
>Calhoun VD, Kiehl KA, Liddle PF, Pearlson GD.
>Biol Psychiatry. 2004 Apr 15;55(8):842-9.
>Institute of Living, Olin Neuropsychiatry Research Center, 200 Retreat
>Avenue, Hartford, CT 06106, USA.
>
>BACKGROUND: Among the most prominent features of schizophrenic brains
>are abnormalities in auditory cortex structure and function,
>particularly in the superior temporal gyrus (STG). In this study, we
>attempted to examine auditory cortex function using an intrinsic,
>task-uncorrelated measure. METHODS: Using functional magnetic resonance
>imaging data, we calculated synchronous hemodynamic independent maps
>(SHIMs) of auditory cortex in patients with schizophrenia and matched
>healthy control subjects while they performed an auditory oddball task.
>RESULTS: Patient SHIMs revealed greater synchrony in ventral and medial
>STG regions (including auditory association Brodmann area [BA] 42);
>control SHIMs had greater synchrony in dorsal and lateral STG regions
>(which did not include BA 42). A within-participant subtractive
>comparison of these two sets of regions differentiated schizophrenic
>from healthy control subjects with 97% accuracy initially (further
>validated by a retest of the healthy control subjects) and performed
>with 94% accuracy in a confirmatory study of new subjects scanned at a
>different site. CONCLUSIONS: These results shed new light on STG
>functional differences in schizophrenia, suggest that aberrant patterns
>of coherence in temporal lobe cortical regions are a cardinal
>abnormality in schizophrenia, and have the potential to provide a
>powerful, quantitative clinical tool for the assessment of schizophrenia.
>
>--
>Tony Miller
>Eaton-Peabody Laboratory, Massachusetts Eye and Ear Infirmary
>243 Charles St, Boston, MA 02114
>ajmiller(at)mit.edu | (617) 510-3629 | http://tonymiller.info