Prior Knowledge of Target Direction and Intended Movement Selection Improves Indirect Reaching Movement Decoding

Area of Science:

• Neuroscience
• Motor Control
• Computational Neuroscience

Background:

• Previous research indicates dorsal premotor cortex (PMd) target direction information enhances neural decoders for movement planning.
• The efficacy of such decoders in complex tasks with obstacles, requiring indirect reaching, remains unexplored.

Purpose of the Study:

• To investigate the encoding of target direction and intended movement selection in PMd neural activity during obstacle-avoidance tasks.
• To compare the decoding performance of movement trajectories using different neural decoders incorporating varying levels of prior knowledge.

Main Methods:

• Recorded spike activities from the PMd of two monkeys performing a delayed obstacle-avoidance task.
• Examined neural population activity for encoding of target direction and intended movement selection during movement planning.
• Compared decoding performance using three mixture of trajectory models (MTM): no prior knowledge, target direction only, and both target direction and intended movement selection.

Main Results:

• Neural activity in the PMd encodes both target direction and intended movement selection during planning.
• Quantitative analysis confirmed the presence of both movement planning parameters in neural signals.
• The trajectory decoder integrating both target direction and intended movement selection demonstrated superior performance.

Conclusions:

• Prior knowledge of target direction and intended movement selection from the PMd significantly enhances hand trajectory decoding.
• This approach is effective for improving decoding performance in indirect reaching movements within complex, obstacle-impeded tasks.