27 Thalamus Flashcards
Which embryonic section of the brain does the thalamus develop from?
diencephalon
What tracks are found in the genu of the internal capsule?
corticobulbar
What are the inputs and outputs of the anterior nucleus and the lateral dorsal nucleus. What general function does it serve?
limbic system inputs and cingulate gyrus outputs– functions as a part of the papez circuit with roles relating to general mood and consolidation of memories
What are the inputs of the mediodorsal nucleus? What general function does it serve?
olfactory cortex and spinothalamic tract inputs are projected to distinct areas with the olfactory cortex projecting to the the insular cortex for taste and the other tracts project to the prefrontal cortex regarding thoughts comparing environment to previous experience and planning next actions and ventromedial prefrontal cortex which is responsible for emotional tone
What are the inputs and outputs f the pulvinar and lateral posterior nuclei,
inputs from the superior colliculus, pretectum and retina as well as the somatosensory and association cortex come in and most are projected back to the visual association cortex for visual responsiveness, orientation and focus; lesion can lead to spatial neglect
What are the inputs to the ventral lateral nucleus? What is their general function?
inputs from the cerebellum are relayed to the primary motor cortex and motor association cortices, the general function is to direct limb position and sequence of movement; lesion can lead to contra hemiataxia
What are the inputs to the ventral anterior nucleus? What is their general function?
inputs from the globus pallidus, substantia nigra head to the premotor cortex for planning of movement, lesion can lead to choreiform movements
What are the inputs to the ventral posterior lateral nucleus? What is their general function?
VPL receives input from spinothalamic tract and the medial lemnicscus regarding info about somatosensory from the body including 2pt touch and pain and sends output to the somatosensory cortex (areas 3,1,2), general function is to convey sensory information from the body to the cortex
What are the inputs to the ventral posterior medial nucleus? What is their general function?
VPM receives input from the face via the trigeminal thalamic tract TTT and taste information from the solitary thalamic tract. Outputs of taste head to the insular cortex while somatosensory head to the somatosensory cortex; general function is to relay sensory information from the face to the cortex (note: VPM is only lightly myelinated compared to VPL)
What are the inputs to the medial geniculate? What is their general function?
receives auditory mixed bilateral auditory information from the inferior colliculus and outputs head to the auditory cortex, transverse gyri and amygdala; general function is to handle bilateral auditory information and lesion can lead to subtle auditory deficits
What are the inputs to the lateral geniculate? What is their general function?
input comes from the retinal ganglion cells, cortical thalamic tracts, interneurons, thalamus, pretectum and reticular nuclei and the are projected to the visual cortex and the amygdala; is general function is “encoding” of a raw image; lesion will lead to contralateral hemifield deficit
What are the inputs to the centromedian geniculate What is their general function?
inputs come from the globus pallidus and the substantia nigra, spinal , reticular (generally widespread nuclei) and outputs go to generally widespread non-specific cortical outputs ; its general function is for arousal (muted for sleep)
Anterior part of the thalamus is oxygenated by which vessel(s)/ branch(es)
tuber-thalamic (also the hypothalamus) with is branch of the posterior communicating artery
The posterior part of the thalamus is served principally by which vessels/branches
primarily thalamogeniculate a. branch of the posterior cerebral artery
Infart of vessels supply the thalamus lead to this syndrome which manifest with these 3 symptoms.
thalamic pain syndrome: allodynia, hyperalgesia an hyperpathia
