Pathways And Subcortical Regions And Cranial Nerves Flashcards
Pathways Brain stem Cerebellum Limbic system Basal ganglia Cranial nerves
All involved in neural processing of speech
The brainstem is
Channel for sensory and motor pathways
The Limbic system is
Structures within cerebrum involved in emotions, motivations, memory and adaptive functions
Limbic system is composed of
Cingulate gyrus
Hippocampus
Amygdala
And more
Hippocampus lies deep within
Temporal lobe and consolidates information from short and long term memory
Hippocampus is affected in
Alzheimer’s disease
Amygdala is attached to
Hippocampus and processes fearful emotions
Cerebellum has two hemispheres and connects to brainstem via
3 pathways
The cerebellum ensures
Coordination of movement (important for balance) and damage to this affects production of steady movement
Cerebellum is involved in
Coordination of the various muscle groups to produce a smooth flow of speech and swallowing
Damage - slurring of speech
The cerebellum is the region of the brain that’s plays an important role in the
Integration of sensory perception and motor output
Attention, music and language
Cerebellum and speech
Engaged in the control of up to 100 or so vocal tract muscles engaged in speech production
Cerebral connections include
Projection tracts and association tracts
Projection tracts are corticobulbar and corticospinal and involve
Long axons and cortex to brainstem/spinal cord
Association tracts are arcuate fasciculus and are
Intrahemispheric (within and between lobes)
Arcuate fasciculus connects
Speech and language cortical areas in frontal, temporal and parietal loves
Corticobulbar/nuclear tract
Bulbar-brainstem
Fibres originate in primary motor cortex (cell bodies upper motor neurons)
End in brainstem
Fibres for control of facial, jaw, tongue, velopharyngeal and laryngeal muscles connect with lower motor neurons
Corticospinal tract fibres originate in
Primary motor, pre motor, supplementary motor cortex (cell bodies)
End in spinal cord (lower motor neurons)
Subcortical nuclei is composed of
Basal ganglia and thalamus
What are the basal ganglia?
Group of nuclei (cell bodies)
Involved in motor control, motor learning and behaviour/emotions
Basal ganglia involved
Striatum (caudate and putamen)
And globus pallidus
Involved in input or output nuclei
Basal ganglia processes movement (muscles of face, larynx, tongue and pharynx)
Main site of dopamine release
Damage can result in involuntary movement (lack of coordination)-Parkinson’s disease
Thalamus is made up of
Hypothalamus Epithalamus Pre thalamus Dorsal thalamus And relays station between au cortical areas and cortex
Thalamus relays sensory information
Almost all sensory systems have thalamic nuclei
Thalamus and language
It is involved in language processing and verbal short term memory
Damage - deficits in memory, attention and reduced spontaneous speech
Neural pathway of speech
Intention-ideation-perception Linguistic~symbolic processing-longuistic form (wernickes area) Motor speech performing (Broca's) Coordination Execution (motor cortex)
Cranial Nerves for speech and swallowing : cranial nerve v- trigeminal- sensory and motor nerves with three divisions
- Ophthalamic
- Maxillary- both sensory: touch, pressure, pain from mid and upper face, maxillary teeth, sinuses
- Mandibular- sensory: touch and pressure from lower teeth, skin of lower face and two thirds of tongue, pinna
Motor: innervate a jaw closing muscles (DIGASTRIC, palatal tensor, tensor tympani and mylohyoid)
Cranial nerve Vii: facial-sensory and motor nerves
Sensory: touch, pressure, taste, pain from mid and upper face, maxillary teeth, sinuses
Motor: innervate all muscles of facial expression, the Stapedius. Produces saliva
Orbicularis Oris, mentalis, levator Anguli Oris etc
Cranial nerve Viii: auditory-vestibular nerve
Sensory nerves( carries information from both cochlea and vestibular apparatus of inner ear to brainstem)
Cranial nerve ix: glossopharyngeal- sensory and motor nerves
Sensory: touch, pressure from posterior tongue, parts of pharynx, pinna. And ear drum(inner surface)
Motor- innervates stylopharyngeus (swallowing)
Cranial nerve X: vagus
Sensory and motor nerves
Sensory: touch, pressure from larynx, pharynx
Motor: innervates pharyngeal constrictor, palatal levator, intrinsic muscles of the larynx and palatoglossus
Cranial nerve xi: spinal accessory nerve
Motor nerves
Motor: innervates sternocleidomastoid and trapezius
Cranial nerve X11: hypoglossal
Motor nerves
Motor:innervates all intrinsic tongue muscles and all but one extrinsic
Cranial nerves for other function: cranial nerve I: olfactory
Sensory nerves that run posteriorly to cortex (temporal lobe)
Other function of Crania nerve II: optic
Sensory nerves that sends electrical impulses from retina to visual cortex (occipital lobe)
Another function for cranial nerve III: oculomotor
Motor nerves that move eyeball up and down
Another function of cranial nerve IV: trochlear
Motor nerves that moves eye up, down, round and side to side
Another function for cranial nerve VI: abducens
Motor nerves that turn eyeball to side of head
Neural control of swallowing
Nearly all structures are same as involved in speech except esophagus
Primary motor cortex Pre motor cortex Primary sensory cortex Insula Basal ganglia Thalamus Cerebellum
