Chapter 5 Flashcards
(33 cards)
Receptor Cells
Specialized cell that responds to a particular energy or substance in the internal or external environments and converts the energy into an electrical potential across its membrane
Labeled LInes
Concept that each nerve input to the brain reports only a particular type of information
Generator Potential
local change in the resting potential of a receptor cell in response to a stimuli (may initiate an action potential)
Sensory Transduction
Process in which a receptor cell converts the energy in a stimulus into a change in the electrical potential across its membrane
Pacinian Corpuscle
“lamelated corpuscle” skin receptor cell that detects vibration and pressure
Meissner’s Corpuscle
“tactile corpuscle” skin receptor cell that detects light touch, responds to changes in stimuli
Merkel’s disc
Skin receptor cell that detects light touch, responding to edges and isolated points on a surface
Ruffini Corpuscle
skin receptor cell that detects stretching of the skin
Free nerve ending
axon that terminates in the skin and has no specialized cell association with it. Detect pain and/or changes in temperature.
Somatosensory system
Set of specialized receptors and neural mechanisms responsible for body sensations such as touch and pain
Receptive field
Stimulus region and features that affect the activity of a cell in a sensory system
Sensory adaptation
Loss of receptor response as a stimulation is maintained
Phasic Receptor
Receptor in which the frequency of action potentials drops as the stimulation is maintained
Tonic Receptor
Receptor in which the frequency of action potentials declines slowly or not at all as the stimulation is maintained
Central modulation of sensory information
Process in which higher brain centers such as the cortex and thalamus, suppress some sources of sensory information and amplify others
Dorsal Column System
Somatosensory system that delivers most touch stimuli via the dorsal columns of spinal white matter to the brain
Dermatome
Strip of skin innervated by a particular spinal nerve
Primary sensory cortex
region of cortex that receives most of the information about a certain sense from the thalamus
Nonprimary sensory cortex
“secondary sensory cortex” receive direct projects from the primary sensory cortex for a certain sense
Primary Somatosensory Cortex
Postcentral gyrus of the parietal lobe where sensory inputs from the body surface are mapped
Polymodal neuron
Neuron where more than one sensory system converges
Synesthesia
Condition in which the stimuli in one modality evoke the involuntary experience of an additional sensation in another modality.
Nociceptors
pain receptors, activated by different chemicals
Transient Receptor Potential 1 and 2 and A delta fibers/C fibers
1 - report rise in temperature to warn us of danger, starts around 90 degrees F
2 - detects even higher temperature receptors startin gat around 122 degrees F
TRP2 are found on A delta fibers which are large in diameter and myelinated
TRP1 receptors consist of the thin and un-myelinated fibers called C fibers.
