Parkinson's Disease and Sequential Working Memory

Parkinson’s disease (PD) is associated with significant executive dysfunction. In a series of recent studies our group has highlighted the crucial role of altered brain oscillations (assessed with EEG) and regional brain function (assessed with fMRI) in these deficits. One significant finding is the correlation between altered parietal alpha and theta oscillations and the impairment in sequencing tasks in PD patients, as revealed through EEG recordings during a picture ordering task. Furthermore, our studies involving PD patients with subthalamic nucleus stimulation have shown that it impairs sequence processing, affecting both language and memory tasks, as evidenced by a slower performance with stimulation on compared to off. Another study highlighted the role of substantia nigra integrity in correlating with basal ganglia function and sequencing performance, indicating that damage to this area could lead to deficits in sequential working memory, mediated by basal ganglia dysfunction. These findings collectively suggest that specific neural markers and mechanisms, such as oscillatory activity and regional brain integrity, play a pivotal role in the cognitive impairments seen in PD, particularly in tasks requiring the maintenance and manipulation of sequences. These insights are critical for developing targeted interventions that may help mitigate some of the cognitive deficits associated with PD.