Effect of Microstimulation of the Superior Colliculus on Visual Space Attention

Abstract

We investigated the effect of microstimulation of the superficial layers of the superior colliculus (SC) on the performance of animals in a peripheral detection paradigm while maintaining fixation. In a matching-to-sample paradigm, a sample stimulus was presented at one location followed by a brief test stimulus at that (relevant) location and a distractor at another (irrelevant) location. While maintaining fixation, the monkey indicated whether the sample and the test stimulus matched, ignoring the distractor. The relevant and irrelevant locations were switched from trial to trial. Cells in the superficial layers of SC gave enhanced responses when the attended test stimulus was inside the receptive field compared with when the (physically identical) distractor was inside the field. These effects were found only in an "automatic" attentional cueing paradigm, in which a peripheral stimulus explicitly cued the animal as to the relevant location in the receptive field. No attentional effects were found with block of trials. The transient enhancement to the attended stimulus was observed at the onset and not at the offset of the stimulus. Electrical stimulation at the site corresponding to the irrelevant distractor location in the SC causes it to gain control over attention, causing impaired performance of the task at the relevant location. Stimulation at unattended sites without the presence of a distractor stimulus causes little or no impairment in performance. The effect of stimulation decays with successive stimulations. The animals learn to ignore the stimulation unless the parameters of the task are varied.

Acute oxytocin improves memory and gaze following in male but not female nursery-reared infant macaques

“…The nucleus basalis of Meynert is one structure with a high density of OT receptors, a region that provides important input to the neocortex, in particular the visual cortex (Gattass et al 2014), involved in recognition memory (Aigner et al 1987), and the basolateral amygdala and which may contribute to some aspects of selective attention and attentional effort, functions that are sensitive to OT treatment (Ebitz et al 2013). Interestingly, dense OT binding was also found in the superior colliculus (Freeman et al 2014).…”

A Role for the Superior Colliculus in Decision Criteria

“…We also used a VR5 schedule of reward to ensure the animals responded as accurately as possible without expecting a reward on each trial (Ferster and Skinner, 1957). We reasoned that on a FR1 schedule, if the stimulation altered the animals' percept, behavior would habituate, or worse, monkeys would develop a strategy to counteract the influence of the stimulation, giving a false readout of the effects of stimulation (Cicmil et al, 2015;Basso and Liu, 2007;Liu and Basso, 2008;Gattass and Desimone, 2014;Murphey and Maunsell, 2007;Murphey et al, 2009). Similarly, we observed that performing stimulation experiments every day resulted in adaptation, so we switched to performing electrical stimulation experiments randomly 2-3 days a week.…”

Prefrontal Corticotectal Neurons Enhance Visual Processing through the Superior Colliculus and Pulvinar Thalamus

“…In addition to direct corticocortical projections, there are also corticotectal neurons projecting to the superior colliculus (SC), a structure important for directing visual attention as well as controlling eye/body movements (Duan et al, 2015;Felsen and Mainen, 2008;Goldberg and Wurtz, 1972;Ignashchenkova et al, 2004;Knudsen, 2018;Kopec et al, 2015;Kustov and Robinson, 1996). In primates, microstimulation of a specific location in the SC improves visual performance at the corresponding region of visual space (Cavanaugh and Wurtz, 2004;Gattass and Desimone, 2014;M€ uller et al, 2005), whereas local pharmacological inactivation severely impairs performance (Krauzlis et al, 2013;Zé non and Krauzlis, 2012). However, compared with corticocortical pathways, whether and how corticotectal neurons contribute to top-down attention is much less understood.…”