integration Flashcards
how does the superior colliculus interact with emotional motor system?
PAG- reaction to things in environment as a reflex. fear, freezing, etc.
why do we have a non-conscious pathway to superior colliculus?
the inputs get integrated with other sensations e.g. auditory, motor and sensory, to direct body, head, neck and eye. sco also contributes to avoidance behaviour.
what is the equivalent structure of scol in non-mammals and what does it do?
optic tectum, for simple prey-predator functions like pecking, noticing shadow. the optic tectum is much larger than scol.
what are the layers of scol and their function?
superficial for visual input, intermediate and deep for multisensory input e.g. visual, somatosensory, auditory and motor output.
what inputs and outputs does the superficial layer regulate?
superficial layer-receives direct retinal ganglion cell input. ALSO, visual cortex’s processed info via corticocollicular.
It projects TO thalamus-LGN and pulvinar (visio-body position and also eye movement), TO cortex e.g. frontal eye fields (cortical pre-motor area for eye movement),
ALSO, to BRAINSTEM : pretectal nucleus (pupillary eye reflex, lens accomodation and eye movement), and parabigeminal nucleus which is interconnected with amygdala and used for fear responses.
what layer of scol controls this: reflexive orientation of eyes and head to take in visual stimuli.
superficial layer
what are the inputs to intermediate and deep layers of scol?
spinal and trigeminal nucleus areas for somatosensation.
ALSO, to superficial layer of sCol
To inferior col for audition
To cerebellum for balance and eye position and proprioception,
To cortex for sensory areas.
what are the outputs from intermediate and deep layers of scol?
cortical areas for controlling eye movement e.g. frontal eye fields, and pulvinar, also to bs reticular formation and spinal cord ventral horn. Also to paramedian pontine RF for eye movements.l
what is the projection from scol deep layers to brain stem?
to paramedian pontine reticular formation which coordinates eye movement via CN3/4 and 6.
what tract projects from scol deep layers to ventral horn?
tectospinal -head movement.
where does reticulospinal tract originate and what is its function?
originates in RF and synapses on ventral horn to coordinate head, neck, eye, posture position and complex patterned actions like walking and maintaining muscle tones.
what is the function of paramedian pontine reticular formation?
generates eye movements via cranial nerves 3/4/6. Scol projects to this.
when is multisensory stimulus strongest?
when each modality is presented at the same time and place=in register, OR when each modality stimulus makes sense according to prior learning AKA coherent
T/F unimodal cortex receives input from other unimodal or polymodal cortices.
true.
what are the areas associated with multisensory info?
posterior parietal cortex (close to S1), premotor cortex.
