Thesis defense – Tomás Garnier Artiñano

Thursday 20 November / 14:30 - 17:00

Venue : CARF

Defense in English

Tomás Garnier Artiñano

Team : Neural Basis of Perception
IINS

Title

Characterisation of the spatiotemporal organisation of cholinergic input in the somatosensory cortex during tactile detection

Abstract

Understanding how the brain detects sensory inputs is a key challenge in neuroscience. Brain states exert a powerful and dynamic influence over the perception of sensory stimuli, with neuromodulatory systems playing a crucial role in regulating these states. The perceptual threshold, defined as the lowest stimulus intensity detectable half the time, varies with context, behavioural state, experience, and mood. However, the mechanisms controlling this threshold remain largely unknown.

Previous studies have demonstrated that cholinergic inputs modulate cortical activity, influencing the detection of sensory stimuli. Traditionally, neuromodulation was thought to have a widespread and uniform impact throughout the brain. However, anatomical evidence suggests that basal forebrain cholinergic neurons offer targeted innervation, potentially enabling localised modulation. There is limited evidence regarding the dynamics of cortical cholinergic modulation and its relevance to sensory perception.

In my thesis, I characterise the spatiotemporal organisation of cholinergic activity in the somatosensory cortex (S1) of mice engaged in tactile detection, by employing a whisker-based tactile detection task. I tested the role of S1 cholinergic activity in the mouse’s sensitivity to detect tactile stimuli showing how the activity patterns of this neuromodulator change behaviour.