Cues to move increased information in superior colliculus tuning curves

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Systems Neuroscience

Background:

• Shifts in spatial attention enhance neuronal responses to sensory stimuli.
• Cues to shift gaze affect sensory responses in the superior colliculus, a key area for eye movement control.
• Gaze and attention shifts are linked, suggesting shared neural mechanisms.

Purpose of the Study:

• To investigate how top-down signals, specifically cues to move the eyes, influence neuronal sensory responses.
• To explore the role of altering neuronal discharge rate variability in this process.
• To understand the impact of saccadic eye movement cues on superior colliculus neuronal activity.

Main Methods:

• Measured spatial tuning of superior colliculus neuronal activity.
• Compared neuronal responses in trials with and without cues to make saccadic eye movements.
• Analyzed changes in tuning curve width and neuronal discharge variability.

Main Results:

• Saccade cues altered tuning curve widths (both increases and decreases observed).
• Information conveyed by neuronal discharge about the stimulus increased with saccade cues.
• Increased information arose from decreased trial-to-trial variability at tuning curve flanks, not increased firing rates at peaks.

Conclusions:

• Top-down signals from eye movement cues can modulate sensory responses in motor areas by changing neuronal discharge variability.
• This mechanism provides a novel pathway for cognitive control over sensory processing in the superior colliculus.
• Findings support theoretical models of cognitive-motor interactions.