High / low IQ in schizophrenia

Abstract
BACKGROUND: Schizophrenia patients are typically found to have low IQ both pre- and post-onset, in comparison to the general population. However, a subgroup of patients displays above average IQ pre-onset. The nature of these patients’ illness and its relationship to typical schizophrenia is not well understood. The current study sought to investigate the symptom profile of high-IQ schizophrenia patients.

METHODS: We identified 29 schizophrenia patients of exceptionally high pre-morbid intelligence (mean estimated pre-morbid intelligence quotient (IQ) of 120), of whom around half also showed minimal decline (less than 10 IQ points) from their estimated pre-morbid IQ. We compared their symptom scores (SAPS, SANS, OPCRIT, MADRS, GAF, SAI-E) with a comparison group of schizophrenia patients of typical IQ using multinomial logistic regression.

RESULTS: The patients with very high pre-morbid IQ had significantly lower scores on negative and disorganised symptoms than typical patients (RRR=0.019; 95% CI=0.001, 0.675, P=0.030), and showed better global functioning and insight (RRR=1.082; 95% CI=1.020, 1.148; P=0.009). Those with a minimal post-onset IQ decline also showed higher levels of manic symptoms (RRR=8.213; 95% CI=1.042, 64.750, P=0.046).

CONCLUSIONS: These findings provide evidence for the existence of a high-IQ variant of schizophrenia that is associated with markedly fewer negative symptoms than typical schizophrenia, and lends support to the idea of a psychosis spectrum or continuum over boundaried diagnostic

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I had an IQ of 124 many many years ago. I’d be afraid to know what it is now. :dizzy_face:

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I’m on the latest Cambridge brain science site but am reluctant to upgrade to the paid version after my previous experiences with such sites. It’s a shame that there isn’t a site that offers a good range of games with a cognitive assessment for free.
I just don’t see what I’ll get out of the paid version given that the time pressured model on offer with these kind of sites isn’t geared to getting the best out of me.

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I was above 120 too,
Fell to 115 after much psychosis and while still very shakey - in other words not well at all
My therapist did the test

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Ok but I can’t find where we see our scores relative to everyone else, it only shows me my scores and I don’t know what they mean

Yeah, even in just the last five years or so I’ve had noticeable memory deficit issues. Numbers have always been a problem for me and now it’s like my brain shuts down at the sight of numbers…
I believe that it’s the stress of all my issues that has eaten away at my brain. It’s like Swiss cheese…

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I had an IQ of 122 in college 33 years ago. I think it is hovering around normal now but, I am not sure because these internet IQ tests are not accurate.

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My personal experience bears out the conclusion of this study. I’ve lived at an assisted living center for the mentally ill for 15 1/2 years. About 40 residents stay here, and a lot of people come and go. So, I have a good sample size from which to extrapolate. My experience tells me that, yes, on average, sz’s IQ’s are lower than normal. However, ever so often a very intelligent person will come through here. One night someone posted an IQ test on this site, and just about everybody scored much higher than average on the test. And I really don’t think the test was biased or skewed in any one way.

My son, who has sz, is brilliant. One example is that in high school he took AP Statistics. While in class he made up a code to take notes so his classmate would stop copying him. Mid-semester he dropped out of the class because he didn’t like the teacher, but took the AP test when it was offered. The highest score on AP tests is a 5, and he got a 4. He has always had above average intelligence.
I worry about him. I worry that his ability to figure things out and contain and use information will decline as he gets older.

I have only taken internet IQ tests but I have had done other things which suggest that I have a high IQ. Also I’ve done things that made me think I have a low IQ like get a low score on the physics GRE. So maybe I would fit into the high IQ category.

I don’t think you iQ goes down. Your ability to function and reason maybe but the disease can’t take your intelligence

Tomcat it can. I should be world chess champion. The disease harms my brain awfully.

I’m at around 100 but can express myself very clearly when I talk, so other people get the impression that I’m higher functioning than I actually am. Appearances matter…if you cut your hair, shave and talk half way straight then it goes a long way.

If you do their IQ test it’ll give you a comparison, or do a Google search for the average scores for the type of test you did.

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Well I have a pretty good case of the illness and my judgement and decision making ability is definitely impaired due to delusions and reality perception problems but I certainly haven’t lost my smarts.

You must have a severe case.

I have no idea what my IQ is. It’s above 100. My psychiatrist estimated mine to be 110-120. For me, it’s really been hard to get my IQ tested. I have Aspergers too.

There is a theory that people with higher IQ have a prevalence of dementia later in life but it is more dramatic and progresses quicker than people’s with lower IQ. The probable explanation of that fact is that they have more to “spare” so then the functional distortion is present later in life. At the same time the problems within the brain start in the same time as others therefore their decline is more rapid when the dementia symptoms are already there. I wonder how it would be in longitudinal studies with sz population. Can be similar case…

that’s called delusions of grandeur or grandiose delusions.

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Very interesting study. I agree with all 3 results of it. I have no negative or disorganized symptoms. I have excellent global functioning and insight. I also showed higher levels of manic symptoms for a long time.