The Nervous System Flashcards
What does the nervous system do?
What basic functional unit carries this out?
Responds to stimuli
Transmits impulses
Controls every function in the human body
Via neurons
What does the CNS consist of? What is its function?
Brain and spinal cord
Receives, processes and acts in information in the environment
What is the function of the PNS?
Connects CNS to areas outside of the nervous system
Connections made via cranial nerves and spinal nerves
Describe the weight and development of the brain
Weighs 3 lbs
Reaches maximum size at the age of 6
Development is not complete until the early 20s
Peripheral extensions are cranial nerves
Describe the spinal cord and its extensions.
Extends from the brain stem and through the neck and back
Peripheral extensions are spinal nerves
What is the largest part of the brain?
Cerebrum
What does the cerebrum function to do within the brain?
Conscious thought processes, intellectual function, memory storage and processing, motor functions
Receives information from the human environment, process it, shares it with other areas, and coordinates a response. It also stores information for future use.
What are the 4 lobes of the cerebrum and their functions?
Frontal: Movement, personality, emotions, motivation, judgment, planning
Parietal: sensations, spatial awareness
Temporal: hearing olfaction, taste, memory
Occipital: vision and visual processing
What part of the brain works independently?
No part of the brain works independently
Neurological pathways connect each lobe
What are the functions of the wrinkles on the cerebral surface? What are they called? When do they form?
Gyrus (gyri): elevated cortical tissue, have different function (motor, senses etc)
Sulcus (sulci): shallow groove of cortical tissue, form important landmarks
Both form during development
What are Brodmann’s Areas?
Scientists classified the cortex into over 50 functional areas
Each has its own physiological function and pattern of connections
What is contained in the diencephalon? What are their functions?
Thalamus: relays center for info coming from brain (sorting system)
Hypothalamus: unconscious brain functions, ANS, endocrine, mood and behavior (control panel)
What additional structures are part of the diencephalon?
Nuclear structures: (basal ganglia) enable the regulation of movement
Limbic system structures: determine personality, mood emotions
What is the function of the brainstem?
Conveys various brain pathways between hemispheres, spinal cord and cerebellum
Contains nuclei for cranial nerves
Centers for breathing, heart rate, and arousal
Coordinate motor activity
What is the function of the cerebellum?
Program movement
Connections with vestibular system (balance, adjustment of eye movements with head movements)
Receives signals from cerebrum to program movement, signals to the rest of the body.
What is CNS tissue made up of?
White (axons and pathways) and gray (cell bodies/nuclei and synapses) matter
What is the spinal cord function and location?
Extends from lowest part of brainstem to lower back
Conveys sensory info from body to brain via thalamus and brainstem
Conveys motor info from motor cortex of cerebrum to body.
Describe the anatomy of a neuron.
Cell body: metabolic center
Dendrites: convey impulses towards cell body
Axon: convey impulses away form cell body
Describe myelin and its function.
Made up of protein and fat
Insulates the axon
Enhances conduction of nerve impulses
How are neurons connected?
Connect (synapse) to other neurons
Connect with receptors in various tissues
Describe functional pathways.
Can consist of single or multiple neurons
Multiple neurons form bundles
Pathways can overlap
Describe afferent brains pathways.
Brings information into the brain
Consists of sensory information
◦ General senses (pain, temperature, fine touch, pressure, position, vibration) (CNS)
◦ Special Senses (5 senses)
Describe efferent brain pathways.
Acts on the information brought into the brain (autonomic and somatic)
◦ Motor (influences muscles)
◦ Visceral (influences glands or organs)
Where are general sensations received and processed?
Parietal lobe
Compare somatic and autonomic NS.
Somatic: voluntary
Autonomic: involuntary, sympathetic (fight or flight), parasympathetic (rest and digest), hypothalamus
