Transcript Brain Higher Functions

Brain Higher Functions
• Diencephalon
• Cerebellum
• Cerebral
Hemispheres
Cerebral
hemispheres
Cerebellum
“2-oval skull”
(includes regions of higher functions)
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Diencephalon
(integrates conscious and unconscious activity)
• Between cerebral hemispheres
• Mostly thalamus and hypothalamus
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Thalamus
Diencephalon
(relays sensory information and emotional state)
• Five groups of nuclei
– Anterior group—limbic system
– Medial group—hypothalamus
emotion center to cerebrum
frontal lobe
– Ventral group—touch and
proprioceptive information
relayed to cerebral cortex
– Posterior group—optic and
auditory information to cerebral
cortex
– Lateral group—emotional state
feedback from limbic system;
integrates with sensory
information
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Limbic system
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Diencephalon
Limbic system
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Diencephalon
Hypothalamus
Diencephalon
• Superior to pituitary gland (gland is in
sella turcica)
• Connected to pituitary by infundibulum
stalk
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Diencephalon
Hypothalamus function
• Feeding reflexes—licking, swallowing, etc.
• Subconscious skeletal muscle movements—facial
expressions, sexual movements
• Autonomic center—control medulla oblongata nuclei for
cardiovascular, respiration
• Secretes oxytocin that stimulates smooth muscle of uterus,
mammary glands and prostate
• Regulates body temperature
• Controls pituitary gland by hormonal secretion—pituitary in
turn regulates many hormonal endocrine functions
• Produces emotions/sensations/drives: e.g. thirst, hunger
(not really “sensations” from periphery)
• Coordinates autonomic response to conscious input—
thought of fear produces accelerated heart rate, etc.
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Pineal gland
• Regulates Cycles
• Secretes melatonin
which helps regulate
circadian and
reproductive cycles
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Diencephalon
Cerebellum
(posture and movement)
• Oval at back of cranial cavity
• Convoluted surface of neural
cortex (like cerebrum)
• Huge branching Purkinje
cells—each cell gets input
from 200,000 synapses
• Internal branching looks like
tree—called “arbor vitae (tree
of life)
• Damage leads to “ataxia”—
disturbance of muscular
coordination
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Cerebrum
(processing central for somatic/conscious information)
• Two cerebral
hemispheres separated
by longitudinal fissure
(sagittal plane)
• Central sulcus divide
(coronal plane) separates
frontal lobe from parietal
lobe
• Horizontal lateral sulcus
(in transverse plane)
separates frontal lobe
from temporal lobe
• Parietal-occipital sulculs
separates parietal lobe
from occipital lobe
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Cerebrum
Cerebrum overall organization
• Left side receives somatic
sensory and controls somatic
motor of right side of body
(and vice versa)
• Two hemispheres have
different specialized areas
(not symmetrical)
• Correspondence of functions
with regions is difficult—lots
of overlap and ability to “fill in”
if areas are damaged
• Corpus callosum is bundle of
axons that link two sides
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Cerebrum
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Cerebrum
Cerebral function in brief
• Basal nuclei/ganglia (sometimes considered part of midbrain)
– Deep in hemispheres
– Subconscious control of skeletal muscle
– Rhythmic movements—overall walking coordination
• Frontal Lobe (primary motor cortex)-voluntary control of
skeletal muscle
• Parietal lobe (primary sensory cortex)—conscious
perception from skin—touch, pressure, pain
• Occipital lobe (visual cortex)—conscious perception of
visual field
• Temporal lobe (auditory cortex and olfactory cortex)—
conscious perception of sound and smell
• All Lobes—integration and processing of sensory input to
initiate conscious motor output
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Cerebrum
Human Anatomy and Physiology I, Frolich, Higher Brain Functions
Interactive overview of basic
regions of brain from PBS
[link]
Human Anatomy and Physiology I, Frolich, Higher Brain Functions