Theory of mind (ToM) is the ability to represent one's own or another's mental states and has been found to be impaired in many psychiatric disorders. Our objective was to compare ToM abilities of patients with obsessive-compulsive disorder (OCD) with healthy controls and to investigate the relation between some illness features, other cognitive functions and ToM abilities of patients.

Thirty OCD patients and age, sex and education matched 30 healthy controls were compared according to their performances on ToM tasks (including first and second order false belief, hinting task and double-bluff task), verbal memory processes test, Weschler memory test (WMT) (logical memory, visual reproduction and digit span sub-tests), stroop test.

Patients’ performances were worse than healthy controls on all of the ToM tasks, but the results were significant for only for double-bluff task (t = −3.992, df = 36.157, p < 0.01). Performance on double-bluff task was significantly and positively correlated with visual reproduction-immediate recall (r = −0.411, p < 0.05) and visual reproduction-delayed recall (r = 0.478, p < 0.05), hinting task was significantly and positively correlated with verbal memory (r = 0.481, p < 0.05).

These results show “basic” ToM abilities of OCD patients are generally preserved, but they show significant reduction in their “advanced” ToM abilities, which seem to be related to their reduced memory capacities. The possible reasons for the relation between memory and ToM impairments, as well as the clinical significance of ToM deficits in OCD are discussed.

Early life stressful events cause long-term neural changes that are associated with psychiatric disorders.

Early life manipulations focus on commonly the impact of remaining separate from the mother in a specific period of time. The maternal odor is required for pups to approach the mother for nursing. What happens when there is a mother that smell like a real mother but does not take care her own pups?

To investigate the fake mother effects on adult rat's behavioral changes, NMDR2B protein level changes in prefrontal cortex and hippocampus.

Wistar rats were used. Fake mother (n:13), early handling (n:12), maternal separation (n:14) and control (n:12) were the study groups. A fake mother is an object that smells like a real dam. When the real mother is separated from own pups fake mother stays with the pups for an hour. Manipulations were made during the postnatal first 14 days. Behavioral tests (social interaction test, elevated plus maze, novel object recognition test) were made between postnatal 62 and 78 days. NMDAR2B protein levels in prefrontal cortex and hippocampus were evaluated by using ELISA at postnatal 78 days.

In social interaction test, fake mother group exhibited less social behavior and more aggressive behavior than the other groups. Their long-term memory functions were the lowest. NMDAR2B protein levels in the hippocampus increased in rats that exposed to early stressful life events.

These results support that being raised by fake mother increases aggressive behavior and decrease social behavior in adulthood.

The authors have not supplied their declaration of competing interest.