Adrenergic Modulation of Visually-Guided Behavior

Abstract

Iontophoretic application of norepinephrine (NE) into the primary visual cortex (V1) in vivo reduces spontaneous and evoked activity, without changing the functional selectivity of cortical units. One possible consequence of this phenomenon is that adrenergic receptors (ARs) regulate the signal-to-noise ratio (SNR) of neural responses in this circuit. However, despite such strong inhibitory action of NE on neuronal firing patterns in V1, its specific action on visual behavior has not been studied. Furthermore, the majority of observations regarding cortical NE from in vivo recordings have been performed in anesthetized animals and have not been tested behaviorally. Here, we describe how micro-infusion of AR agonists/antagonists into mouse V1 influences visually-guided behavior at different contrasts and spatial frequencies. We found that cortical activation of α1- and β-AR produced a substantial reduction in visual discrimination performance at high contrasts and low spatial frequencies, consistent with a divisive effect. This reduction was reversible and was accompanied by a rise in escape latencies as well as an increase in the group averaged choice variance as a function of stimulus contrast. We conclude that pharmacological activation of cortical AR regulates visual perception and adaptive behavior through a divisive gain control of visual responses.

Adaptive Choice Biases in Mice and Humans

“…Variability at the circuit level is generated by many neurophysiological mechanisms that include the stochastic nature of synaptic transmission with relevant interactions across large neural populations and with distributed neuromodulation effects ( Dinstein et al, 2015 ; Trevino et al, 2019 ). Where exactly does the brain implement regulation for choice variability?…”

“…We characterized visual contrast responses by using static sine-wave gratings (0.04 cycles/degree) with multiple contrasts. Our screens were gamma-corrected to ensure linearly increasing intensity scales ( Trevino et al, 2019 ). We also tested the discriminative capacities of the mice by using a set of equiluminant images with variable structural similarity among them (SSIM).…”

Noradrenaline modulates neuronal and perceptual visual detectability via β-adrenergic receptor

“…We demonstrated that the topical administration of propranolol onto the surface of V1 improved behavioral performance of the VD task. Recently, two studies investigated β-AR modulation on perceptual visual ability (Mizuyama et al 2016 ; Treviño et al 2019 ). Treviño et al ( 2019 ) showed that the micro-infusion of isoproterenol, a β-AR agonist, in V1 decreased the visual discriminability of mice, indicating that the activation of β-AR in V1 worsens visual discriminability, which is consistent with our present study.…”

“…In vision, some studies reported that β-AR modulates perceptual visual sensitivity, but the effects were inconsistent. Treviño et al ( 2019 ) reported that the local administration of β-AR agonist on the primary visual cortex (V1) worsens the task performance of mice performing the two-alternative forced-choice (2-AFC) visual discrimination task in a water maze. On the other hand, Mizuyama et al ( 2016 ) showed that the systemic administration of a β-AR antagonist impairs the visual detectability of rats performing the 2-AFC visual detection (VD) task in an operant chamber.…”

“…They found that the activation of α 1 - and α 2 -ARs mainly facilitated both the visual response and spontaneous firing, but the activation of β-AR facilitated or inhibited the visual response of each cell. These neuromodulatory effects in V1 could contribute to the improvement or impairment of perceptual sensitivity in behaving animals (Mizuyama et al 2016 ; Treviño et al 2019 ). However, it still remains unknown how NA modulates the neuronal activity in V1 via β-ARs or how the adrenergic modulation affects the visual perception of awake animals.…”