Temporal Haemodynamic Measures of Mood and Work Load Effects on Working Memory Performance

Neuroimaging studies show that mood affects working memory performance (WMP) through changes in haemodynamic activity (HA) in the prefrontal cortex (PFC). However, it is unknown how WMP and HA is modulated by increasing working memory load (WML) under different mood states. We investigate the interactive effects of mood state (psychological factor) and WML (difficulty factor) on WMP and HA with N-back task using functional near-infrared spectroscopy (fNIRS) neuroimaging of the PFC in 31 healthy subjects (HS). Our study reveals distinct mood-dependent modulations of HA with increasing WML which correlate with decreasing WMP. The influence of mood on performance is greatest at high WML.