Sensory Prioritization in Rats: Behavioral Performance and Neuronal Correlates

Abstract

Operating with some finite quantity of processing resources, an animal would benefit from prioritizing the sensory modality expected to provide key information in a particular context. The present study investigated whether rats dedicate attentional resources to the sensory modality in which a near-threshold event is more likely to occur. We manipulated attention by controlling the likelihood with which a stimulus was presented from one of two modalities. In a whisker session, 80% of trials contained a brief vibration stimulus applied to whiskers and the remaining 20% of trials contained a brief change of luminance. These likelihoods were reversed in a visual session. When a stimulus was presented in the high-likelihood context, detection performance increased and was faster compared with the same stimulus presented in the low-likelihood context. Sensory prioritization was also reflected in neuronal activity in the vibrissal area of primary somatosensory cortex: single units responded differentially to the whisker vibration stimulus when presented with higher probability compared with lower probability. Neuronal activity in the vibrissal cortex displayed signatures of multiplicative gain control and enhanced response to vibration stimuli during the whisker session. In conclusion, rats allocate priority to the more likely stimulus modality and the primary sensory cortex may participate in the redistribution of resources.

Superior colliculus modulates cortical coding of somatosensory information

“…Together, these studies suggest that the effect of SC activation on vS1 through POm may be to enhance and sustain cortical sensory signals and thereby emphasize and direct attention to salient sensory information. Consistent with this idea, enhanced population activity is observed in vS1 during simple forms of attention such as sensory prioritization (Lee et al, 2016) and temporal cueing . These findings are in line with earlier work in primates (Muller et al, 2005;Cavanaugh et al, 2006;Lovejoy & Krauzlis, 2010;Zénon & Krauzlis, 2012;Herman & Krauzlis, 2017) as well as attentional gain modulation seen in mouse visual cortex and thalamus (Wimmer et al, 2015;McBride et al, 2019).…”

Superior colliculus modulates cortical coding of somatosensory information

“…Together, with our findings, these studies suggest that the effect of SC activation on vS1 through POm may be to enhance and sustain cortical sensory signals and thereby emphasize and direct attention to salient sensory information. Consistent with this idea, enhanced population activity is observed in vS1 during simple forms of attention such as sensory prioritization 51 and temporal cueing 52 . These findings are in line with earlier work in primates [53][54][55][56][57] as well as attentional gain modulation seen in mouse visual cortex and thalamus 58,59 .…”

Developmental plasticity of texture discrimination following early vision loss in the marsupialMonodelphis domestica

“…Humans are naturally visual animals (Preuss 2003), however, individuals who experience vision loss, especially in cases of congenital deficits, can become highly effective at using tactile and auditory based strategies along with perceptual learning that manifest as heightened sensitivity to stimuli mediated by the spared senses (Goldreich and Kanics, 2003;Wong et al, 2011;Voss, 2011; for review see Bavelier and Neville, 2002;Kupers and Ptito , 2011;Merabet and Pascual-Leone, 2010;Renier et al, 2014;Ricciardi et al, 2014). Finally, even without the loss of a sensory receptor array, any given individual might rely more heavily on one sensory strategy over another in different settings, depending on the ongoing availability and behavioral relevance of sensory information (Montero, 1997;Lee et al, 2016); for example, touch and hearing may be prioritized over vision upon entering a dark room or at night, when visual information is not readily available.…”