Subthalamic stimulation affects homophone meaning generation in Parkinson's disease.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) in individuals with Parkinson's disease (PD) has often been associated with reduced verbal fluency performance. This study aimed to directly assess semantic switching as a function of STN stimulation in PD participants with the Homophone Meaning Generation Test (HMGT). Seventeen participants with PD who had received STN DBS completed the HMGT in on and off stimulation conditions.

Estimation of neuronal firing rates with the three-state biological point process model.

In the subcortex of the human brain, neuronal firing events are stochastic and the inter-arrival times of action potentials (APs) are highly irregular. It has been shown that stimulation of the subthalamic nucleus (STN), a small subcortical structure located within the basal ganglia, can help ameliorate the motor symptoms associated with Parkinson's disease (PD). However, success of image guided stereotactic surgery is reliant upon the refinement of the anatomic target (in this case the STN) based on micro-electrode recordings (MERs) of background activity and firing rate.

Lexical-semantic inhibitory mechanisms in Parkinson's disease as a function of subthalamic stimulation.

Inhibitory control may be affected by Parkinson's disease (PD) due to impairment within the non-motor basal ganglia-thalamocortical circuits. The present study aimed to identify the effects of chronic stimulation of the subthalamic nucleus (STN) on lexical-semantic inhibitory control. Eighteen participants with PD who had undergone surgery for deep brain stimulation (DBS) of the STN, completed a picture-word interference (PWI) task and the Hayling test in on and off stimulation conditions.

Semantic and affective priming as a function of stimulation of the subthalamic nucleus in Parkinson's disease.

Lexical-semantic and emotional processing deficits have been associated with Parkinson's disease. This study investigated automatic and controlled lexical-semantic processing, the automatic activation of emotional evaluations, and the processing of words conveying negative and neutral emotional connotations in a combined affective and semantic priming paradigm. Eighteen participants with Parkinson's disease who had undergone surgery for deep brain stimulation (DBS) of the subthalamic nucleus (STN) completed a lexical decision task at short and long stimulus onset asynchronies (SOAs), during on and off stimulation conditions.