title: Whisker somatosensation in the mouse superior colliculus: pathways and behaviour
creator: Isaías-Camacho, Emilio Ulises
subject: ddc-500
subject: 500 Natural sciences and mathematics
subject: ddc-570
subject: 570 Life sciences
subject: ddc-610
subject: 610 Medical sciences Medicine
description: Animals can react quickly to stimuli in their environment, e. g. orienting towards a stimulus or escaping a threat. The superior colliculus(SC) is a phylogenetically old midbrain brain structure producing swift orientation and defence movements to enhance the individual’s survival. However, these movements could be wasteful without adaptation or even modulation. Mice rely on their whiskers to perceive and interact with their environment. The whisker-related connectivity to SC, involving the layer 5 (L5) of motor cortex (MC) and barrel field cortex (BC), and the brainstem (Bs), as well as from collicular recipient neurons (RNs) was described by different viral strategies, including an intersectional viral approach, revealing novel long-range projections from SC. I developed a behavioural paradigm to quantify mice’s SC-dependent evoked behaviour upon an unpredictable whisker puff. Pharmacologically blocking the SC reduced the puff evoked behaviour and showed that SC is an important node in the orientation circuit of the brain. Building on the collicular whisker network, the cortical influence to modulate and adapt SC-mediated orientation behaviours was tested by a. optogenetically manipulating cortical axons in SC, and b. optogenetically manipulating RNs directly. Modelling of the sensorimotor transformation showed that the SC performs part of the computation for orientation movements and that activation of a specific RNs population is a likely candidate for modulating and even adapting SC-dependent behaviour. My results reveal that top-down modulation of SC-dependent behaviour is achieved through specific neural populations in SC, controlled by L5-MC inputs and reflects the high level of natural alertness mice need to escape predators and feed.
date: 2025
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserver/37500/1/Dissertation_IsaiasCamacho.pdf
identifier: DOI:10.11588/heidok.00037500
identifier: urn:nbn:de:bsz:16-heidok-375004
identifier:   Isaías-Camacho, Emilio Ulises  (2025) Whisker somatosensation in the mouse superior colliculus: pathways and behaviour.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/37500/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng