Perceptual decisions

When we feel confident in a perceptual decision, that decision is more likely to be correct. How does the brain assess the quality of perceptual decisions? Here, we test two connected hypotheses. First, that perceptual confidence relates to the structure of population activity in the sensory cortex. And second, that this relation differs from the one between sensory activity and perceptual decisions. To this end, we studied neural population activity in the primary visual cortex of macaque monkeys performing a task that reveals the animal's subjective sense of perceptual confidence. Specifical

How the activity of sensory neurons supports perceptual decisions remains one of the central questions of systems neuroscience. Two primary frameworks guide the field’s thinking on this question. One framework, guided by ideas of information maximization, redundancy reduction, and efficient coding, focuses on the decision-related information represented by neural responses and how it is extracted from sensory populations. In another framework, based on the Bayesian brain hypothesis, sensory responses represent posterior beliefs about the outside world, which then guide decision-making. Interes

Our brains predict future sensory input based on their current beliefs about the world around us, but interpreting prediction errors can be challenging in a volatile environment because they can be caused by stochastic sensory noise or by outdated predictions. Noisy signals should be integrated with prior beliefs to improve precision, but the two should be segregated when environmental changes render prior beliefs irrelevant. Bayesian inference provides a statistically optimal solution to deal with such problems of causal uncertainty [1]. However, the method quickly becomes memory intensive an

The role of the whisker-related primary somatosensory cortex (wS1) in perceptual decisions remains a topic of ongoing debate. While previous research has linked wS1 to stimulus detection, discrimination, and the coordination of whisker movements during active touch and associative learning in simple stimulus detection tasks, its contribution to behavior becomes crucial as cognitive load and perceptual demands escalate. The gap-crossing task has thus emerged as a model for studying wS1 functions, requiring freely-moving mice to actively employ their whiskers to locate a target platform after a

…and its use in forming accurate perceptual decisions. In particular, it is unclear how activity distributed across cortical areas and frequency bands encodes information synergistically or redundantly, and how these emergent properties of interactions across areas relate to perception. Here, we aim to measure synergy and redundancy during an audiovisual task at the mesoscale level in auditory, visual

…information, essential to inform perceptual decisions. However, the particular link between rhythmic stimulus features, neuronal activity and perceptual behavior remains elusive. In our work, we address this relationship

Multisensory processing in the brain is pivotal for forming perceptual decisions. While the primary sensory areas were traditionally considered strictly unisensory, recent rodent research has unveiled significant interactions between the auditory and visual cortices. Notably, V1 neurons were found to be hyperpolarized by auditory noise bursts or show sensitivity to the temporal coherence of audiovisual stimuli. These findings indicate that primary sensory regions possess the computational capacity for multisensory processing, although the impact of such cross-modal interactions on decision-mak

Humans constantly make perceptual decisions on human faces and voices. These regularly come with the challenge of receiving only uncertain sensory evidence, resulting from noisy input and noisy neural processes. Efficiently adapting one’s internal decision system including prior expectations and subsequent metacognitive assessments to these challenges is crucial in everyday life. However, the exact decision mechanisms and whether these represent modifiable states remain unknown in the general population and clinical patients with psychosis. Using data from a laboratory-based sample of healthy

Dorsolateral prefrontal cortex (DLPFC) and dorsal premotor cortex (PMd) are two association brain areas implicated in decision making. However, whether these brain areas have similar or distinct decision-related dynamics remains an open question. In addition, anatomical studies suggest considerable connectivity heterogeneity between DLPFC areas and parietal lobe, temporal lobe, and ventrolateral prefrontal cortex. Whether different areas within the DLPFC also demonstrate distinct decision-related dynamics is also an open question. We addressed these open questions by comparing the neural dynam

…a high degree of confidence in a perceptual interpretation, that interpretation is more likely to be correct than when we feel less confident. Here we ask how neural population activity in sensory cortex informs confidence in perceptual decisions. We used multilaminar electrode arrays to record population activity in the primary visual cortex of a macaque monkey performing a perceptual confidence task. Specifically, the animal judged the orientation of ambiguous stimuli (“clockwise” vs “counter-clockwise”) and simultaneou

Visual decisions typically require accumulation of uncertain sensory information to make inferences about the state of the world. This inference process is complicated by the fact that the state of the world can change, which often requires adjustments in how sensory information is accumulated. Previous work has modeled optimal inference in these changing environments [1-2]. One key feature of these models is a leakage of accumulated evidence, where the leak rate depends on environmental stability. For example, in more unstable environments, an increased leak rate helps remove pre-change evide

To survive in the uncertain world, humans and animals must pick the right task to perform in each situation and flexibly switch between tasks when they infer that the environment has changed. Yet such flexibility comes at a cost. Task performance decreases when the relevance of the task is uncertain. Here we present multiple lines of evidence from monkey electrophysiology, human psychophysics, and artificial neural networks demonstrating a neuronal mechanism that inflicts a cost of flexibility. In a behavioral paradigm designed to measure and manipulate subjects’ belief about the relevance of

The brain makes decisions by accumulating evidence until there is enough to stop and choose. Neural mechanisms of evidence accumulation are well established in association cortex, but the site and mechanism of termination is unknown. Here, we elucidate a mechanism for termination by neurons in the primate superior colliculus. We recorded simultaneously from neurons in lateral intraparietal cortex (LIP) and the superior colliculus (SC) while monkeys made perceptual decisions, reported by eye-movements. Single-trial analyses revealed distinct dynamics: LIP tracked the accumulation of evidence on

Perceptual decisions are ubiquitous and essential in life, and even in their simplest forms open a window into the neural mechanisms underlying cognition. However, the properties of decision mechanisms inferred in simple behavioral paradigms are not independent of the properties of employed stimuli and task. One key task property is the type of information provided by a single stimulus, which can be either stationary or dynamic. Stationary paradigms are based on evidence with fixed central tendency, often obscured by noise, whereas in dynamic paradigms the mean of the evidence can vary within