internal brain

thalamus

thalamus

routes all sensory information from periphery cerebellum and brainstem to appropriate sites in cortex

epithalamus

contains pineal gland, receives input from CNII

hypothalamus

contains autonomic nuclei and connects the nervous system to the endocrine system

amygdala

modifies behavior to satisfy internal needs (feeding, sexual desire, anger, etc)

can also be modified by internal environment (blood pressure, heart rate, fear, etc)

hippocampus

related to learning and memory; input from amygdala

commissural fibers

cross midline (decussate) to connect two cerebral hemispheres)

projection fibers

transmit info from periphery to cortex via thalamus

internal capsule

motor fiber tracts from cortex to spinal cord and periphery

basal ganglia

consists of the globus pallidus, putamen, caudate nucleus, subthalamic nucleus and substantia nigra

communicates with the cerebral cortex to help regulate and direct voluntary movement

lesion=dyskinesia

brain stem

contain nuclei and nerve roots for each of the cranial nerve

contain autonomic nuclei to regulate basal functions

contain ascending and descending fiber tracts

contain fibers that communicate between cerebellum and cerebrum

Midbrain

nuclei for CN III

corpora quadrigema

corpora quadrigema

superior colliculus and inferior colliculus

superior colliculus

coordinates the visual reflex (input from CN II)

inferior colliculus

coordinates the auditory reflex (input from CN VIII via olivary nucleus)

reticular formation

maintains consciousness, autonomic motor output, and muscle tone

solitary nucleus

forms nucleus tractus soltarius which is primary visceral sensory relay (cardiac, respiratory, GI, endocrine)

ascending fibers of reticular formation

“keep the cortex awake” and regulate circadian rhythms

input from spinothalamic tracts, CN nuclei, and cerebellum

descending fibers of reticular formation

input from cortex, basal ganglia, and limbic system

regulate cardiorespiratory drive, neuroendocrine secretions, and maintain muscle tone

olivary nucleus

coordinates motor learning patterns

part of pons and auditory system

receives input from CN VIII and cerebellum

*relay station for auditory and vestibulocochlear info

nucleus gracilis

relay somatosensory and some proprioception from lower limbs to thalamus

nucleus cuneatus

relays somatosensory and some proprioception from upper limbs to thalamus

cerebellum

coordinates muscular activity and controls posture/equilibrium

lesion=ataxia

limbic system

emotional brain

lesion= anger, depression, memory loss, etc