The Cerebellum & Basal Ganglia Flashcards
Function of Cerebellum
Evaluates difference from intended action and actual action while a moment is in process
Cerebellum receives input from____,____,____.
cerebral cortex, brainstem, and spinal cord
Cerebellum send _______, forming a _____
projections back to them, vast loop
Cerebellum - Input
Cerebral cortex: synapse in the pontine nuclei of the pon first.
Direct sensory input: vestibular, muscle spindles, other mechanoreceptors.
Other brainstem input: inferior olive, the locus coeruleus
The locus coeruleus
Send modulatory inputs for learning & memory
Cerebellar Lesion
dysmetria and the decomposition of movement
Motor systems of cerebellar disease
wide gait, irregular staggering steps, instability of trunk
Results of cerebellar disease
lateral veering or falling
can also be seen w/ severe loss of proprioception本体感觉
Output from cerebellum
Cerebral cortex to deep cerebellar nuclei and onto motor cortex via the thalamus
2 types of input neurons of the cerebellar circuit
Mossy fibres
Climbing fibres
Mossy fibres
Synapse on granule cells颗粒细胞.
Axons of granule cells from parallel fibres which synapse on Purkinje cells
Climbing fibres
from inferior olive
Synapse directly on Purkinje cells
Purkinje cells
Provide the output of the cerebellar cortex through inhibitory synapses;
How many granule cells and climbing fibres can Purkinje cell receives?
One Purkinje cell can receive input from over a million granule cells (civergence会聚) BUT ONLY 1 climbing cell
The function of Basal Ganglia
基底神经节
A collection of forebrain structures involved in motor control, especially in the regulating & planning of movement.
Provide excitatory signals to the motor cortex which modified by dopaminergic signals.
Basal Ganglia receives input from ___ and projects back to ____ through _____.
the cortex, cortex, thalamus
Basal Ganglia circuit
Influence brainstem output and ultimately 最终 neurons of the spinal cord
Organization of the Basal Ganglia
Consist of 4 major interconnected nuclei found in the white matter of the cerebellum
The 4 major interconnected nuclei
striatum 纹状体 (caudate & putamen)
globus pallidus 苍白球
Substantia nigra 黑质 (pars compacta & pars reticulata)
Sub-thalamus nuclei 丘脑核
Input to the Basal Ganglia
caudate & putamen are input nuclei of the basal ganglia
ONLY the primary visual cortex & auditory cortex do not project to the datemen
Datemen also receives dopaminergic inputs from the substantia nigra pars compacta
Output to the Basal Ganglia
Datemen send output through globus pallidus & substantia nigra pars reticulata
Globus pallidus - external segment & internal segment
external - part of the pathway of neurons that inhibits movement
internal - inhibitory for movement initiation运动启动抑制
Output of the basal ganglia
is sent on the superior colliculus, subthalamus nuclei, the thalamus and eventually back to the cerebral cortex
Activity of the Basal Ganglia
MC (motor cortex)->Datemen->GPi (苍白球internal)->Th (Thalamus)->MC
MC->Datemen->Substantia nigra pars reticulata-> Superior colliculus
