The enlarged cava septi pellucidi (CSP = 6 mm in length) have been reported as a reliable marker of an underlying neuropsychiatric disease or disorder. Differences in the dimensions of cava longer than 6 mm associated with a neuropsychiatric impairment could be of possible clinical and forensic significance.

We obtained 479 brains from autopsied persons (310 males and 169 females, aged 22–89 years) and observed that 110 brains (75 males and 35 females) had CSP, of which the length of CSP was equal to or longer than 6 mm on 69 (49 males and 20 females) of them. These cava were classified into four groups depending on the past medical histories of the autopsied person: five without neuropsychiatric history (asymptomatic CSP), 25 schizophrenic patients, 22 alcoholics, and 17 with a past head trauma (symptomatic CSP).

The linear parameters of CSP (i.e. length, width) of the symptomatic and asymptomatic groups were measured and were statistically analyzed. Analysis revealed that the cava in the group of schizophrenic patients were significantly longer and wider.

Discriminant function analysis was used to derive a mathematical formula to classify CSP into one of the groups obtained based on width measurements of the cavum.