Nervous system 2 Flashcards
Cephalization, the clustering of neurons and
interneurons in the anterior part of the animal, is
apparent in
A) Hydra
B) Cnidarians
C) sea stars
D) Planaria
D (flatworms)
What does the central nervous system consist of? What does it do?
The brain and spinal cord.
Spinal cord conveys information to and from the brain, and can produce reflexes independent of the brain.
What does the peripheral nervous system consist of? What does it do (overall)?
Nerves and ganglia
Transmits information to and from the CNS
What is the difference between afferent neurons and efferent neurons?
Afferent - transmit information to the CNS (input)
Efferent - transmit information away from the CNS (output)
What are the two systems of efferent neurons? What do each of these systems do?
Motor system - voluntary; carries signal to skeletal muscles
Autonomic nervous system - involuntary; regulated smooth muscles and cardiac muscles
What are the two divisions of the autonomic nervous system and what do they each do?
Sympathetic division - “fight or flight”
Ex. Accelerates heart, dilates pupil of eye, stimulates glucose
Parasympathetic division - “rest and digest”
Ex. Slows heart, constricts pupil of eye, stimulates gallbladder
What is the enteric nervous system? (not too important to know)
Controls digestive movement
What are the three major regions of the brain?
Forebrain (cerebrum & diencephalon in adult), midbrain, and hindbrain (both make up the brainstem)
How has the forebrain evolved in the animal phylogeny?
Mammals have the largest forebrain. As you go down the phylogenetic tree, the forebrain size increases.
What does the cerebellum do?
Coordinates movement and balance
Receives sensory information about the position of joints and muscles
Regulates motor function (hand-eye coordination)
What happened to the woman without a cerebellum? What key trait of the brain does this show?
She was deficient in movement/balance, regulating motor function, and position of limbs, but otherwise fully functional!
Shows compartmentalization!
What does the diencephalon consist of? What does it regulate?
Consists of the thalamus, hypothalamus, and pituitary gland.
Regulates homeostasis, hunger, thirst, social and sex behaviors, and the fight-flight response
What does the brainstem consist of? What does it mediate?
Consists of the midbrain, pons, and medulla oblongata
Mediates the sending of information to different parts of the brain. Direct information between cereberum and spinal cord
What does the limbic system consist of? What does it do?
Interfaces with diencephalon, brainstem, and cerebrum
Consists of: amygdala, hippocampus, thalamus, and hypothalamus
Functions in emotion, memory, learning, fear, motivation, behavior, and olfaction
What does the cerebrum overall function in? What are the four lobes?
Functions in awareness, language, cognition, memory, and consciousness
4 lobes: frontal lobe, temporal lobe, parietal lobe, and occipital lobe
What does the frontal lobe consist of? What do those two parts do?
Prefrontal cortex -decision making, planning, facial recognition
Motor cortex - control of skeletal muscles
What does the parietal lobe do? How do the two parts connect?
Deals with sense of touch
Signal comes from skin, goes to somatosensory cortex, then goes to sensory association cortex, which integrates the sensory information
What does the occipital lobe do? How do the two parts connect?
Deals with sense of sight
Signal comes from eyes, goes to visual cortex, then goes to visual association cortex, which combines images with object recognition
What does the temporal lobe do? How do the two parts connect?
Deals with sense of sound
Signal comes from the ears, goes to the auditory cortex, then goes to Wernicke’s area, which comprehends language and sounds associated with certain objects
How does the cerebrum function overall?
Receives input from sensory organs, including touch, and sends output signals out in response.
- Primary motor cortex (sends signals out to move body) - frontal lobe
- Primary somatosensory cortex (receives touch signals from the body) - parietal lobe
How does the thalamus (limbic system) function overall?
It directs different types of input to distinct locations in the cerebrum. Physically organizes where signals are coming from.
What does the left hemisphere vs the right hemisphere do?
Left hemisphere - language, math, logical operations
Right hemisphere - pattern recognition, spatial relations, nonverbal thinking (intuition)
What connects the two hemispheres of the brain?
The corpus callosum
In humans, fear, emotion, motivation, olfaction,
behavior, and memory are mediated by the
A) occipital lobes of the cerebral cortex
B) frontal lobe of the cerebral cortex
C) limbic system
D) cerebellum
C
Neural plasticity
The ability of neurons to strengthen/weaken connections through experience. Physical changes in how neurons connect to other neurons, that can be strengthened or weakened by experience. Ex. presence/absence of synapses, or number of synapses
Increasing the amount of receptors _________.
increases the response
What is memory formation mediated by?
The hippocampus in the limbic system and the association corticies
Short term memory
Involves neurons in hippocampus. The strengthening and then weakening of neural plasticity
Long-term memory
Involves neurons in hippocampus and cerebrum. Side note: consolidating memories is thought to occur during sleep.
What are some disorders of the nervous system and what do they do? (Generally)
Schizophrenia - causes hallucinations, delusions
Depression - has 2 forms (major and bipolar)
Drug addiction - brain becomes dependent on drugs
Alzheimers disease - characterized by amyloid plaques
Parkinson’s disease - characterized by muscle tremors
