(Aug. 5, 2013) There are now 20 studies of the brains of individuals with schizophrenia using neuroimaging techniques to determine whether the brains of individuals with anosognosia (poor insight) are different from the brains of individuals who do not have anosognosia (good insight).
Of the 20 studies, 18 reported clear differences and two did not. Two of the positive studies were done on individuals who had never been treated with antipsychotic drugs, so the observed differences clearly were not a drug effect. Thus, using neuroimaging techniques, it is apparent that the brains of individuals with anosognosia are different from the brains of individuals who do not have anosognosia.
Neuroimaging techniques, such as magnetic resonance imaging (MRI) are rather gross measures of the brain. Such studies are done on people who are alive and are like the pictures from an airliner at 20,000 feet; you can see the contours and major features of the land but not the small details.
We now have some of those details. For the first time, a report was recently published on postmortem research on the brains of people with schizophrenia – some of whom had had anosognosia and some did not – looking at their brain cells under a microscope. The research was carried out by a highly experienced Russian group that does neuropathological research under the leadership of Dr. Natalya Uranova at the Mental Health Research Center in Moscow .*
In this research, anosognosia was assessed after death by examining the person’s medical records. Indication of anosognosia included the person’s explicit denial of illness, refusal to take medication, failure to follow treatment plans, and multiple re-admissions. The brains of 24 individuals with schizophrenia were assessed. Nine of them did not have anosognosia (they had good insight and awareness of illness), and 15 exhibited symptoms of anosognosia (fair or poor insight and awareness of illness). The brain areas examined were two parts of the inferior parietal lobule, a brain area known to be involved in insight.
The results of the study showed a 21% reduction in glial cells (specifically obligodendroglia) in the brains of the individuals with anosognosia (fair or poor insight). Those with anosognosia differed statistically from the normal control brains (p=0.04) and at the borderline statistically from those without anosognosia (p=0.055). The brains of the individuals without anosognosia (good insight) did not differ from the normal controls.
Summary: This is the first study that has assessed microscopically the brains of people who have died with schizophrenia, some of whom had anosognosia and some of whom did not. Those with anosognosia had fewer glial (obligodendroglial) cells. Such research is continuing.
For more information about lack of awareness into illness, see our Frequently Asked Questions about Anosognosia page and watch our four-minute video that includes dramatic footage of an accused killer with symptoms of anosognosia being interviewed.
* Vostrikov et al, Reduced obligodenroglial density in the inferior parietal lobule and lack of insight in schizophrenia. European Journal of Psychiatry 27:111-121, 2013.