FIGURE 9.

Conceptual model explaining visuomotor transformations in FEF and SC. A schematic of FEF and SC temporal responses during visual, memory, and motor periods (enclosed in dashed box) and relationship with different visuomotor processing stages are shown. Visual neurons (red) encoded the accurate target position in eye coordinates (T). These neurons receive projections from early visual processing areas. Visuomotor neurons (pink) encoded positions that fell close to T but drawn toward the direction that predicted gaze endpoint in eye‐centered coordinates (G). This visual response likely reflects a stage of visual processing which maps, through a noisy gate, visual information into a priority map of movement goals resulting in the accumulation of errors in behavior (Ɛ _vis). This position is maintained through recurrent connections between frontal and parietal areas (purple box), which also send projections to FEF and SC. This memory maintenance is susceptible to noise (Ɛ _mem), resulting in the diffusion of the attention spotlight (or memorized location). After the GO signal, the most recent memory of the target location is transferred, via a noisy output gate, to the motor circuitry, resulting in additional accumulation of noise (Ɛ _mem‐mot). The motor neurons in FEF and SC send this gaze command to downstream structures, where additional processing for the coordination of effectors and appropriate reference frame transformations (RFT) take place. Adapted from Sajad et al., (2015, 2016)