Auditory P300 study in remittent bipolar child and adolescent population.

Objectives: Previous studies have revealed P300 abnormality in adult bipolar population, both in acute and euthymic phases and also in their first-degree relatives. To the best of our knowledge there are limited data in the child and adolescent bipolar population. In this study we attempt to record P300 amplitudes and latencies of remittent child and adolescent bipolar patients and compare them with normal controls.

Method: 25 remittent child and adolescent bipolar patients and 25 age, sex matched controls were recruited. P300 was recorded using the auditory oddball paradigm.

Results: There was significant increase in latency of P300 at midline, parietal leads, and the frontal and central leads decreased significantly at the parietal and frontal leads in the patient population. Amplitude was more in the patient group as compared to controls.

Conclusion: The present findings of prolonged latency and reduced amplitude of P300 in the remission and the phase of bipolar illness indicate that cognitive processing deficits persist beyond illness and P300 could be a promising candidate endophenotype for future research.