What are sensations?
#NAME?
what are the functions of the nervous system?
1. rapid communication
2. information processing
What are the 3 steps of information processing?
1.
sensory input
: external and internal information from sensory receptors
2.
integration
: interpretation of input, association of input with responses
3.
motor output
: signals from integration center(s) to effector cells
What are afferent neurons?
from periphery to the central nervous system (CNS)
What are efferent neurons?
Motor neurons which carry information away from the CNS to the periphery (innervate effectors)
what is transduction?
stimulus ? sensory receptors ? change in receptor membrane permeability ? receptor potential (graded change in membrane potential)
what problem does transduction solve?
conversion of stimulus energy into a neuronal signal
what is transmission?
if receptor = sensory neuron: it conducts APs to CNS
if receptor =? sensory neuron: sensory neuron generates APs
What is a chemoreceptor?
a sensory cell or organ responsive to chemical stimuli.
what does "type of stimulus" mean?
type of activated receptor
what does "intensity of stimulus" mean?
number of activated receptors -frequency of action potentials
what does "location of stimulus" mean?
location of activated receptors
- timing of receptor activation (for sound and smell)
what does "duration of stimulus" mean?
pattern of action potentials
what are the receptor types?
chemoreceptors
mechanoreceptors thermoreceptors
nociceptors
electromagnetic receptors
- No such thing as pain receptor!
how is information interpreted?
#NAME?
describe sensory reception by hair cells
spontaneously active
- direction of bending of 'hairs' conveys information
What is sensation?
triggered by sensory stimuli
- travels to brain as action potentials (APs) via sensory
pathways
What is perception?
ability to discriminate various aspects of the stimulus
- meaningful interpretation of sensory data
describe perceptions of taste and smell
Chemoreception
- Perceptions of taste and smell are usually interrelated