Neuro 7 - major brain areas/sensory and motor pathways

descriptions of major lobes,

frontal lobe function

contains primary motor cortex, also controls language and personality

parietal lobe function

contains somatosensory cortex

temporal lobe

memory and primary auditory cortex

occipital lobe

primary visual cortex

central sulcus separates

frontal and parietal

parieto-occipital sulcus separates

parietal and occipital

lateral sulcus separates

temporal from both frontal and parietal

transverse fissure separates

cerebellum from cerebrum

brainstem

midbrain, pons, medulla oblongata

diencephalon components

thalamus and hypothalamus

where is brainstemlocated

base of brain in front of cerebellum

3 types of white matter tracts and functions

commissural tracts (connect hemispheres), projection tracts (connect cerebral cortex to other CNS areas outside cerebrum), association tracts (long or short connections between different areas of brain)

example of commissural tract

corpus callosum

example of projection tract

somatosensory tract

example of association tract

arcuate fasciculus (connects brocas and wernickes)

anatomy of primary motor cortex

precentral gyrus

anatomy of somatosensory cortex

postcentral gyrus

corticospinal pathway

somatic efferent

corticospinal pathway upper motor neuron movement

cell body: primary motor cortex
axon: crosses over to opposite side of spinal cord
synapses onto lower motor neuron

corticospinal pathway lower motor neuron movement

cell body: in ventral horn of spinal cord
axon: leaves through ventral root
synapses onto skeletal muscle

damage to primary motor cortex

paralysis/muscle weakness in region of body corresponding to location of damage on the OPPOSITE side

dorsal/posterior column pathway sensory info

fine touch, vibration and proprioception

proprioception

awareness of body in space

neuron one of dorsal/posterior column pathway

cell body: dorsal root ganglion
peripheral fibres run from skin receptors
central fibres travel up spinal cord
synapse onto N2 in the medulla oblongata

what type of neuron is neuron 1 of the dorsal/posterior column pathway

pseudounipolar (cell body stuck out to side)

neuron 2 of dorsal/posterior column pathway movement

cell body: medulla oblongata
axon: crosses to OPPOSITE side and ascends
synapses onto N3 in thalamus

neuron 3 of dorsal/posterior column pathway

cell body: thalamus
axon: ascends to somatosensory cortex
synapses onto appropriate somatosensory neuron

spinothalamic tract sensory info

pain and temperature

neuron 1 of spinothalamic tract

cell body: dorsal root ganglion
peripheral fibres run from skin receptors
central fibres ascend the spinal cord
synapse onto N2 in dorsal horn/spinal cord

neuron 2 of spinothalamic tract

cell body: dorsal horn
axon: decussates via anterior white commissure tract cells
synapses onto N3 in thalamus

neuron 3 of spinothalamic tract

cell body: thalamus
axon: ascends to somatosensory cortex
synapses onto appropriate somatosensory neuron