Central Nervous System Flashcards
Gyri
folds on surface of cerebrum
Sulci
grooves between folds of the cerebrum
Fissures
deep grooves between the folds of cerebrum
diencephalon
area between cerebrum and brainstem
cerebellum
portion of the brain in posterior inferior region that processes coordination and movement
proprioception
position of joints
Wernicke’s Area
specialized area in the brain that helps with understanding speech
Broca’s Area
specialized area in the brain that has to do with producing meaningful speech
Nerves
whitish fiber or bundle of fibers that transmits impulses of sensation to brain or spinal cord, or to the muscles and organs
What does the cell body do?
carries genetic information, maintains neuron’s structure, and provides energy for activities
Dendrites
Fibrous roots that branch out from cell body, receiving and processing signals from axons of other neurons
Central Nervous System
CNS is the processing center of the body; consists of brain and spinal cord
Neurotransmitters
chemical substance that is released at end of nerve fiber by arrival of nerve impulse; when diffused across synapse or junction, causes transfer of impulse to another nerve fiber, muscle fiber, or other structure
axons
long, threadlike part of nerve cell along which impulses are conducted from cell body to other cells
axon terminal
found at terminal ends of axons; typically where synapses with other neurons take place; neurotransmitters stored there to communicate with other neurons via these synapses
sensory nerves
also called afferent nerves; nerve fibers responsible for bringing sensory information from outside world to brain; senses such as vision, hearing, smell, taste, touch, pain, temperature, proprioception
motor nerves
also called efferent nerves; transmits impulses from CNS out to peripheral organs to cause an effect or action
somatic nervous system
voluntary; part of the peripheral nervous system associated with voluntary control via skeletal muscles
autonomic nervous system
involuntary; part of the peripheral nervous system that regulates involuntary physiologic processes, including heart rate, blood pressure, respiration, digestion, sexual arousal; contains three anatomically distinct divisions: sympathetic, parasympathetic, enteric
skeletal muscle
muscle connected to the skeleton to form part of mechanical system which moves limbs and other parts of body
smooth muscle
muscle tissue in which contractile fibrils aren’t highly ordered, occurring in the gut and other organs; not under voluntary control
synapse
junction between two nerve cells; minute gap across which impulses pass by diffusion of a neurotransmitter
myofibrils
very fine contractile fibers; groups of myofibrils extend in parallel columns along striated muscle fibers; made of thick and thin myofilaments, which give the muscles striped appearance
sarcomere
fundamental unit of contraction; region between two z-lines; consists of central A-band (thick filaments) and two halves of I-band (thin filaments)
actin
thin filaments of protein that form with myosin, making up contractile filaments of muscle cells; involved in motion
myosin
thick filaments of fibrous protein that form with actin, making up contractile filaments of muscle cells; involved in motion
main parts of the brain
outer cerebrum, inner diencephalon
diencephalon
thalamus, hypothalamus, epithalamus, subthalamus
cerebrum
largest portion of nervous system; two hemispheres with white matter bridge called “corpus callosum”
describe the surface of the cerebrum
folds called gyri and sulci (grooves), and deeper grooves called fissures
name the 4 lobes
frontal, parietal, temporal, occipital
frontal lobe involved in:
motor movements, concentration, planning, problem solving, smell, emotions
parietal lobes involved in:
process sensory information (but not hearing, smell, and vision)
temporal lobes involved in:
hearing, smell, memory, abstract thought, making judgments
occipital lobe involved in:
processing visual information
name the two fissures and what they divide
longitudinal fissure divides parietal lobes, lateral fissure divides temporal & parietal lobes
central sulcus is located:
midway on lateral aspect of cerebrum, separating frontal from parietal lobes.
thalamus
“relay station”; carries all sensory information to cerebral cortex except sense of smell (carried directly to frontal lobe of cerebral cortex by olfactory nerves); involved in emotions, since connected to the limbic system
examples of sensory information
auditory, visual, motor information
location of hypothalamus
inferior and anterior to the thalamus
hypothalamus
regulates hormones (endocrine system); regulates body temperature, thirst, hunger, sexual drive, involved in emotions, mood, sleep (reticular activating system)
pineal gland
small endocrine gland that secretes melatonin; located posterior to the diencephalon
brainstem
located between cerebral cortex and spinal cord; consists of midbrain, pons, medulla oblongata
medulla oblongata
most inferior portion of brainstem; controls heart rate, respiration, swallowing, vomiting, blood vessel diameter; contain spinal pathways called “tracts” that connect spinal cord to brain
pons
middle section of brainstem; contains spinal cord tracts and nuclei which help control respiration & sleep
midbrain
most superior portion of brainstem; helps process motor and hearing information
reticular formation is located:
throughout brainstem; regulates sleep-wake cycles
limbic system
contains cerebrum, diencephalon; involved in reproduction, memory, emotions; contains cingulate gyrus, portions of thalamus, hypothalamus, mamillary and amygdaloid bodies, hippocampus, nucleus accumbens
limbic system component locations
seems like most of them are located in the diencephalon
What is the autonomic nervous system?
maintains homeostasis in body even when unconscious; “visceral motor system” since ANS sends motor impulses to viscera
How is the ANS divided?
Sympathetic and parasympathetic