Encoding of 2D Self-Centered Plans and World-Centered Positions in the Rat Frontal Orienting Field

Area of Science:

• Neuroscience
• Motor Control
• Cognitive Neuroscience

Background:

• Motor planning research in rodents often struggles to differentiate between self-centered and world-centered spatial representations.
• The frontal cortex, particularly the frontal orienting field (FOF), shows preparatory activity predicting choices.

Purpose of the Study:

• To investigate the reference frames used for spatial information processing in the rat frontal orienting field (FOF) during motor planning.
• To determine if the FOF encodes movement direction in a self-centered or world-centered frame.

Main Methods:

• Rats were trained on a delayed visually guided orienting task with multiple directions and target positions.
• Single unit activity was recorded from the FOF in the secondary motor cortex.
• Population analyses and neural network models were used to analyze spatial representations.

Main Results:

• The FOF encodes two distinct 2D spatial maps: one for movement direction (self-centered) and one for current position (world-centered).
• Individual FOF neurons multiplexed both self-centered and world-centered reference frame variables.
• Neural network models supported that the FOF primarily uses self-centered input for planning signals.

Conclusions:

• The frontal orienting field (FOF) utilizes a self-centered reference frame for planning upcoming movements.
• Despite incorporating world-centered positional information, the FOF's output signals are predominantly self-centered.
• This study clarifies the reference frames involved in motor planning within the rodent secondary motor cortex.