Is there an association between a behavioral measure of working memory and the measures of P300

Background: In recent times, the P300 has been extensively explored to assess cognitive function and contextual knowledge in humans. The main aim of the study is to explore whether the scores obtained in behavioural tests for Working Memory (WM) like the Reading Span Test (RST) is associated with electrophysiological tests like P300. A total of 60 participants in the age range of 18-40 were included in this study, of which 30 participants were included in group 1 who had normal hearing sensitivity, and the other 30 were included in group 2 who had bilateral hearing loss (HI). Participants had normal cognitive functioning and were screened for having normal cognitive abilities using a test. After completing basic hearing assessment tests, RST and P300 were administered. Result: We found a strong positive correlation of P300 amplitude with RST in normal hearing and HI groups. A moderate negative correlation was found between P300 latency and RST in the normal hearing group while a weak correlation was found in the HI group for the same. In both the groups Reaction Time has a strong correlation with amplitude and latency of P300. Conclusion: We may use P300 amplitude to estimate the WM capacity and the latency of P300 may be also essential to evaluate the lexical access capacity of working memory.