8 - General Principles of Sensory Processing, Touch, and Pain Flashcards
(65 cards)
Stimulus
A physical event that triggers a sensory response
Sensory receptor organ
An organ (such as an eye or ear) specialized to receive particular stimuli
Receptor cell
A specialized cell that responds to a particular energy or substance in the internal or external environment, and converts this energy into a change in the electrical potential across its membrane
Adequate stimulus
The type of stimulus for which a given sensory organ is particularly adapted
Specific nerve energies
The doctrine that the receptors and neural channels for the different senses are independent and operate in their own separate ways, and can produce only one particular sensation each
Labeled lines
The concept that each nerve input to the brain reports only to a particular type of information
Sensory transduction
The process in which a receptor cell converts the energy in a stimulus into a change in the electrical potential across its membrane
Generator potential
A local change in the resting potential of a receptor cell that mediates between the impact of stimuli and the initiation of action potentials
Pacinian corpuscle
A skin receptor cell type that detects vibration
Threshold
The stimulus intensity that is just adequate to trigger an action potential at the axon hillock
Coding
The rules by which action potentials in a sensory system reflect a physical stimulus
Range fractionation
A hypothesis of stimulus intensity perception stating that a wide range of intensity values can be encoded by a group of cells, each of which is a specialist for a particular range of stimulus intensities
Somatosensory
Referring to the body sensation, particularly touch and pain sensation
Adaptation
The progressive loss of receptor sensitivity as stimulation is maintained
Tonic receptor
A receptor in which the frequency of action potentials declines slowly or not at all as stimulation is maintained
Phasic receptor
A receptor in which the frequency of action potentials drops rapidly as stimulation is maintained
Central modulation of sensory information
The process in which higher brain centers, such as the cortex and thalamus, suppress some sources of sensory information and amplify others
Sensory pathway
The chain of neural connections from sensory receptor cells to the cortex
Thalamus
The brain regions at the top of the brainstem that trade information with the cortex
Receptive field
The stimulus region and features that affect the activity of a cell in a sensory system
Primary sensory cortex
For a given sensory modality, the region of cortex that receives most of the information about that modality from the thalamus or, in the case of olfaction, directly from the secondary sensory neurons
Secondary sensory cortex or nonprimary sensory cortex
For a given sensory modality, the cortical regions receiving direct projections from primary sensory cortex for that modality
Primary somatosensory cortex (S1) or somatosensory 1
The gyrus just posterior to the central sulcus where sensory receptors on the body surface are mapped. Primary cortex for receiving touch and pain information; in the parietal lobe
Secondary somatosensory cortex (S2) or somatosensory 2
The region of cortex that receives direct projections from primary somatosensory cortex
