Independent basal ganglia populations encode speech production and ambient noise

Latané Bullock and colleagues have published “Independent basal ganglia neural populations encode speech production and ambient-noise levels” in Nature Communications. The study recorded neural activity from the subthalamic nucleus and globus pallidus in DBS patients performing a speech task that used the Lombard effect, the tendency to speak louder in noisy environments, to vary environmental demands.

Two distinct neural populations emerged: one active during speech production and another that tracked background noise levels, including at baseline, with high decoding accuracy. Neither region strongly encoded the intensity of the speech produced. The findings suggest that the basal ganglia use separate codes to monitor the acoustic environment and to control speech output, which may support adaptive communication across varying conditions.

The work continues the lab’s intracranial studies of speech and the subthalamic nucleus in patients undergoing deep brain stimulation surgery. The paper is available at https://www.nature.com/articles/s41467-026-77937-8.