P₃₀₀ auditory wave image and its relation to cognitive function in subjects with marijuana addiction: A cross-sectional study in Cipinang and Pondok Bambu Penitentiary, Jakarta

Subjects with marijuana addiction tend to have cognitive function impairment. Auditory P₃₀₀ wave, a potential objective tool in examining cognitive function, can assess cognitive function in the auditory pathway to the cortex. Cognitive function impairment can be assessed by prolonged latency and decreased amplitude. The present cross-sectional study was conducted between June and August 2012 involving 68 subjects with marijuana addiction. Cognitive function was assessed using Rey Auditory Verbal Learning Test. Subjects were assessed with an auditory P₃₀₀ wave examination using both latency and amplitude. Forty subjects had cognitive function impairment; eight had abnormal P₃₀₀ latency, whereas 60 (88.2%) had decreased amplitudes. There was significant correlation between P₃₀₀ amplitude and cognitive function, but not between P₃₀₀ latency and cognitive function. Marijuana can impair cognitive function, especially related to attention and memory deficit indicated by a decreasing P₃₀₀ amplitude. However, P₃₀₀ latency did not indicate a cognitive function impairment-related abnormality, which could have arisen from an improper range application developed with reference to American subjects. Overall, the results confirmed that cognitive function impairment due to marijuana addiction can be objectively revealed by decreasing P₃₀₀ amplitudes. Further studies are needed to confirm appropriate range application in both adult and pediatric Indonesian populations.