physiology - The Central Nervous System

Central nervous system (CNS) is composed of what

brain and spinal cord

Peripheral nervous system is composed of what

sensory receptors and nerves

how is the Structure of the Brain

Cerebrum

Diencephalon

Midbrain

Hindbrain

what is the frontal primary of

motor area

Primary motor area (Precentral gyrus) =

Voluntary motor control of skeletal muscles

Premotor cortex

Memory bank for skilled motor activities

Motor speech (Broca’s) area

Directs muscles of speech

Frontal eye field

Controls voluntary eye movement

Gustatory cortex

Receives taste information from taste buds

Insula also receives information from viscera, hearing, and smell

Primary sensory area (Postcentral gyrus)

Receives sensory, tactile and proprioceptor input

Somatosensory area

Integrate and analyze input from the primary sensory area

What does the Primary visual cortex and visual association area receive and interpret

visual input

Auditory (cortex and association) area =

Receives and interprets auditory input (i.e. a person’s voice)

Olfactory cortex

Receives input from olfactory epithelium in nasal cavity

where is General interpretive area (Wernicke's area) found

only on left hemisphere

what does the General interpretive area (Wernicke's area) recieve

input from all sensory association areas

General interpretive area (Wernicke's area) function

understanding written and spoken words

Prefrontal cortex function

intellect, complex learning, and personality

where is the Visceral association area found

within the insula

what is the Visceral association area involved in

conscious perception of visceral sensations (i.e. stomach ache)

Basal Nuclei

Gray matter composed of neuron cell bodies located deep within the white matter of the cerebrum

basal nuclei function

allowing intended movements while inhibiting unintended movements

what do the The auditory and visual areas receive

information

auditory and visual Information is sent to what area

Wernicke's area which then formulates a response

The response from auditory and visual information is then sent to

Broca’s area for delivery

Wernicke's aphasia

speech is rapid and fluid but without meaning; “word salad”

Broca’s aphasia

reluctance to speak, and speech is slow and poorly articulated

Conduction aphasia =

Speech is fluent and comprehension is good, but repetition of phrases is slow and labored

what does the limbic system include

a series of nuclei that surround the diencephalon

The hypothalamus is closely associated with what

the limbic nuclei

The “emotional brain” mediates

emotional response and involved in memory processing

Memory is thought to be function of what

several different brain regions

Memory consolidation is the conversion of

short-term into long-term and occurs in the hippocampus

Short-term memory is involved with what lobe

medial temporal hippocampus, amygdala and the cerebral cortex)

Long-term memory

Non-declarative (implicit) memory, Declarative (explicit) memory

Synaptic Changes in Memory

Proposed mechanism for long-term potentiation

in long term potentiation what binds to two different receptors AMPA and NMDA

Glutamate

Dendritic spines

spine-like extensions of dendrites

Most EPSPs are produced where

Dendritic spines

Most EPSPs are produced in the dendritic spines in response to what

glumate

Thalamus

Primary relay station for sensory and impulses to cerebral cortex

Epithalamus

Contains the pineal gland (body) which secretes melatonin to regulate circadian rhythms

what is the Hypothalamus involved with

limbic system to regulate some emotions

what does hypothalamus regulate

pituitary secretions

what rhythms does the hypothalamus regulate

circaidian

Midbrain

A conduction pathway between higher and lower brain centers

mid brain is associated with what 2 dopaminergic neuron systems:

Nigrostriatal system and Mesolimbic system

Nigrostriatal system

projects from substantia nigra and functions in motor coordination

Mesolimbic system

dopaminergic neurons from ventral tegmental area and substantia nigra, and functions in reward

Pons

Transmits information to and from the cerebellum and the cerebrum

pons contains control center for what

respiration

Apneustic

controls intensity of breathing

Pneumotaxic

= inhibitory impulses on inspiration

Cerebellum

Important for coordination of movement

cerebellum receives information from where

proprioceptors (joints, tendons, muscle receptors)

what does the cerebellum work with

cerebral cortex to coordinate movement

Medulla Oblongata

Contain fiber tracts connecting the spinal cord to the brain

what does the medulla oblongata house

autonomic control (vital) centers

The reticular formation

= Series of fibers and nuclei located throughout the brain stem

what does the reticular formation promote

wakefulness

The reticular formation governs what

arousal of the cerebral cortex

The reticular formation enhance what

incoming sensory information coming from thalamus

what is the spinal cord composed of

of the outer white fiber tracts (ascending and descending) and inner gray matter

The functions of the spinal cord

Transmit information between the brain and the periphery… Process simple reflexes

how many cranial nerves are there

12

most cranial nerves are what

mixed nerves

mixed nerves

contain both sensory and motor fibers

the spinal cord is divided into how many segments

31

Reflex arc

Basic functional unit of nervous system and simplest portion capable of receiving a stimulus and producing a response

Reflex

Automatic response to a stimulus

components of reflex

Sensory receptors Sensory neuron Interneuron Motor neuron Effector organ