Background

Differences between verbal and non-verbal cognitive development from childhood to adulthood may differentiate between those with and without psychotic symptoms and affective symptoms in later life. However, there has been no study exploring this in a population-based cohort.

Method

The sample was drawn from the MRC National Survey of Health and Development, and consisted of 2,384 study members with self-reported psychotic experiences and affective symptoms at age 53 years, and with complete cognitive data at ages 8 and 15 years. The association between verbal and non-verbal cognition at age 8 years and relative developmental lag from age 8 to 15 years, and both adult outcomes were tested with the covariates adjusted, and mutually adjusted for verbal and nonverbal cognition.

Results

Those with psychotic experiences (thought interference [n=433], strange experience [n=296], hallucination [n=88]) had lower cognition at both age 8 and 15 years in both verbal and non-verbal domains. After mutual adjustment, lower verbal cognition at age 8 years and greater verbal developmental lag were associated with higher likelihood of psychotic experiences within individuals, whereas there was no association between non-verbal cognition and any psychotic experience. In contrast, those with case-level affective symptoms (n=453) had lower non-verbal cognition at age 15, and greater developmental lag in non-verbal domain. After adjustment, lower non-verbal cognition at age 8 years and greater non-verbal developmental lag were associated with higher risk of case-level affective symptoms within individuals.

Conclusions

These results suggest that cognitive profiles in childhood and adolescence differentiate psychiatric disease spectra.