Search results
Results from the WOW.Com Content Network
Confocal microscope image of cerebellar Purkinje cells expressing tdTomato. These cells are some of the largest neurons in the human brain (Betz cells being the largest), [5] with an intricately elaborate dendritic arbor, characterized by a large number of dendritic spines. Purkinje cells are found within the Purkinje layer in the cerebellum.
The human cerebellum is located at the base of the brain, with the large mass of the cerebrum above it, and the portion of the brainstem called the pons in front of it. It is separated from the overlying cerebrum by a layer of tough dura mater called the cerebellar tentorium; all of its connections with other parts of the brain travel through the pons.
Diagram of the layers of the cerebellar cortex showing a glomerulus in the granular layer. Granule cells receive all of their input from mossy fibers, but outnumber them by 200 to 1 (in humans). Thus, the information in the granule cell population activity state is the same as the information in the mossy fibers, but recoded in a much more ...
There are four paired deep cerebellar nuclei embedded in the white matter centre of the cerebellum. The nuclei are the fastigial , globose , emboliform , and dentate nuclei. In lower mammals the emboliform nucleus appears to be continuous with the globose nucleus, and these are known together as the interposed nucleus .
In the cerebellum, the multipolar basket cells have branching dendrites, which are dilated and knotty. Basket cells synapse on the cell bodies of Purkinje cells and make inhibitory synapses with Purkinje cells. Cerebellar basket cell axons fire inhibitory neurotransmitters such as GABA to Purkinje cell axons, and inhibits the Purkinje cell. [9]
Purkinje fibers take up stain differently from the surrounding muscle cells because of having relatively fewer myofibrils than other cardiac cells. The presence of glycogen around the nucleus causes Purkinje fibers to appear, on a slide, lighter and larger than their neighbors, being arranged along the longitudinal direction (parallel to the ...
Plasticity of the synapse between a parallel fiber and a Purkinje cell is believed to be important for motor learning. [11] The function of cerebellar circuits is entirely dependent on processes carried out by the granular layer. Therefore, the function of granule cells determines the cerebellar function as a whole. [12]
Purkinje cells of flocculonodular lobe → juxtarestiform body of inferior cerebellar peduncle → vestibular nuclei (synapse/termination of cerebellovestibular fibers) → Medial and lateral vestibulospinal tracts (extrapyramidal upper motor neurons) → (synapse) lower motor neurons → skeletal muscle