Lecture 7- Stimulus localisation Flashcards
Give 3 examples of stimulus localisation
orientation of head
smooth pursuit
prediction of prey movement
What are the 3 key brain areas involved in stimulus localisation
retina
dorsal stream in the cortex
superior and inferior colliculus
where do the superior and inferior colliculus receive inputs from
ganglion cells
auditory system
somatosensory system
what is the main function of the superior and inferior colliculus
regulation of saccadic movement
Describe retinotopic maps
organisation whereby neighbouring cells in the retina feed info into next door places in the target structure
what do retinotopic maps allow the brain to do
to process visual info whilst maintaining spacial relationship
Where are retinotopic maps found
primary visual cortex
secondary visual areas
LGN
superior colliculus
what is the orientation reflex
when a new stimulus appears, animals turn their heads in a position suitable for inspection
what does ablation of the optic tectum lead to
no orientation reflex
describe directional excitation
ON/OFF cells respond to movements in some directions but not others
what do direction selective ON/OFF cells receive inputs from
excitation from bipolar cells
inhibition from amacrine cells
what happens to on/off cells in the prefered direction
excitation larger and inhibition smaller and delayed
