LECTURE 27 - closed loop control : blindsight Flashcards
what is the extrageniculate visual pathway ?
aneural pathway in the brain that processes visual information that bypasses the primary visual cortex, (consists of a set of subcortical structures, including the superior colliculus, the pulvinar nucleus of the thalamus, and the accessory optic system)
what can happen if you have a leision to V1 ?
- blindness/partial blindness in one or both eyes
- scotoma and agnosia
- difficulty in perceiving motion, depth, and form
- visual hallucinations or distortions, such as seeing objects that aren’t there / misinterpreting the shape/size of objects
what is a scotoma ?
is a blind spot in the visual field
what is agnosia ?
impaired ability to recognize faces or objects
what is considered an “older pathways” that is dynamic and unexpected ?
extrageniculate pathway
what is a shorter pathway; V1 or extrageniculate pathway ?
extrageniculate (fewer synapses = shorter pathway)
what makes a pathway shorter ?
fewer synapses
what is saccade suppression ?
eyes moving at maximum velocity
what is the double-step paradigm ?
a technique used in neuroscience research to study the neural mechanisms underlying sensorimotor integration, attention, and decision-making
what do they do in the double-step paradigm ?
- adds a second target that appears briefly at a different location before the main target
- the timing of the appearance of the second target is manipulated to influence the saccade trajectory towards the main target.
in the double-step paradigm; 25% of trials =
target “jump” / pertubation
when does a target “jump” occur ?
occurs when eyes are moving at a maximum velocity
which paradigm uses a double step paradigm >
the double-step paradigm closed loop control
can people with lesions participate in this rapid ability to make that motor system connection (hands moving to the new target) ?
no they cannot
who preformed the double-step paradigm graphs ?
goodie et al.