10.4.09

Schizophrenia

Have a look at this picture. What do you see?



Watch this.



A big problem with psychiatry is the lack of objective physical tests to diagnose mental illnesses. Diagnosis is usually done through a structured interview and the psychiatrists assessment of how a person looks and behaves and what they say. This is matched against a pattern of 'signs', what you can see, and 'symptoms', what the patients says, in DSM IV or ICD-10.

Research has just been published that suggests the hollow mask illusion can be used as a test for schizophrenia. Watch the video below for a brief outline of this research.
 


Previous research had demonstrated that people diagnosed with schizophrenia were less fooled by visual illusions than normal controls. The scientists wanted to find out if the 'hollow face' illusion had the same effect. They showed two groups of participants, people diagnosed with schizophrenia and normal controls, pictures of normal faces and hollow mask faces. As they looked at the pictures their brain activity was measured with an fMRI scanner. All 16 non-schizophrenic participants were fooled by the hollow mask illusion and identified it 99% of the time. All 13 participants diagnosed with schizophrenia saw the difference between the normal face and the hollow mask face and only 6% failed to identify the difference. Brain scans identified a difference between the way the schizophrenic participants and normal controls processed visual information. This suggests that people with schizophrenia have a problem connecting two parts of the brain involved in visual processing: a part of the brain that processes visual input and a part of the brain that controls this process. The connection between the sensory and conceptual areas of their brain may be malfunctioning.

This kind of research may eventually lead to the development of valid and reliable tests for schizophrenia.

Link to UCL press release: hollow mask illusion fails to fool schizophrenia patients

No comments: