Topic: pupil diameter

Recent studies show that behaving animals transition between discrete strategies during sensory decision-making and that arousal modulates task performance. However, it remains a challenge to understand (i) the relationships between arousal and task strategy during sensory discrimination and (ii) the neural mechanisms underlying optimal performance states. To address these topics, we combined behavioral, neurophysiological, and computational approaches to uncover the neural mechanisms underlying arousal-dependent sensory discrimination. We implemented two-alternative-choice tasks, prompting mi

Locus coeruleus (LC) activity consists in a sustained low-frequency firing rate (tonic activity), accounting for basal pupil diameter, interspersed with event-driven higher-frequency bursts (phasic activity), accounting for event-related transient changes in pupil diameter. Pupil size measurements are used here as a non-invasive biomarker of LC activity, and to assess its evolution with age. Pupil size was measured in 72 healthy participants (34 young: age = 23.0 years ± 2.6; 38 older: age = 69.3 years ± 6.8), who underwent a 2-minute passive gaze fixation task and a fast object categorization

Schemas are known to facilitate learning and memory consolidation in humans and rodents. However, their role in decision making is not well understood and the effects of task factors like risk, novelty, prior knowledge, arousal and attention are under-explored. We designed a new computer-based experiment where participants could firstly explore a list of different author’s paintings or quotes and then select items with the same authorship. Most participants showed improvement in performance, yet factors, including previous progress, risk and novelty conditions, pupil diameter and heart rate, p

Knowledge of the timing of events is critical for efficient behaviour. Previous work examining the formation of expectations following temporally predictable stimulus sequences has revealed that humans are able to extract regularities, which can improve performance. To determine the underlying neural circuits that drive temporal attention, we established an equivalent behavioural paradigm for mice. We randomize trials with either a long or short delay between a cue and target stimulus, where one delay type occurs with a higher frequency. This allowed for the formation of expectations based on