Forebrain: Thalamus, internal capsule Flashcards
In order to get to he cortex, it needs to first go through the ____
thalamus
Describe where the thalamus sits
Lies one on each side, deep in each hemisphere. Each thalamus has specific areas that specific types of information goes to
eg; all info going to the auditory cortex first goes the the MGB of the thalamus
What is the purpose of the Medial Geniculate body?
the auditory pathway conveys information from the ear on opposite side, passes through and terminates onto the MGB.
MGB project up and carry that info to the primary auditory complex. (completes ear to cortex pathway) ‘tonotopically’
Why are there some cells projecting also from the primary auditory cortex to the MGB?
These cells control what information goes up to the cortex.
This allows you to modulate what you do hear ‘tuning out at a party’.
This applies to all areas of the cortex!
What is the purpose of the Lateral Geniculate body?
the optic pathway conveys information from the eye on opposite side, passes through and terminates onto the LGB.
Very complex processing, then goes to primary visual cortex visuotopically.
The ‘hearing part’ of the thalamus
MGB
The ‘seeing part’ of the thalamus
LGB
The VA and VL gets input from?
The ‘computer system’s in the brain that are involved in movement control;
- basal ganglia
- Cerebullum
Once movement information has terminated at VA and VL, where does it then go?
Projects to the MOTOR CORTEX to influence how the motor cortex sends impulses down to the lMN on the opposite side of the spinal cord to contract muscles just the right way.
What subdivides the thalamus and into what compartments?
A motorway of fibres that forks out subdivides that thalamus into medial, lateral and anterior nuclear groups.
The VP nucleus gets input from?
Sensory pathways on touch and pressure.
Once sensory movement information has terminated at VP, where does it then go?
projects info to the primary somatosensory cortex/ PoCG.
This area is highly organised, and so is the VP area!!
The thalamus areas are very organised just like the areas of the ….
Cortex!
How can we specialise what we feel!
You can specialise areas of feeling!
“how does your big toe feel”
We aren’t aware of this
Why are we so concerned about injury to the thalamus
It provides all the input to the thalamus, so if injured then information can not reach it’s destination!
