Chapter 8 terms Flashcards
Sensory receptor organs
Organs specialized to detect a certain stimulus.
Receptor cells
cells within the organ convert the stimulus into an electrical signal.
Adequate stimulus
the type of stimulus to which a sensory organ is particularly adapted.
Doctrine of Specific nerve energies
This idea says that receptors and neural channels for different senses are independent. Each sense uses a different “nerve energy”
Concept of labeled lines
This idea says that the brain recognizes distinct senses because action potentials travel along separate nerve tracts.
Sensory transduction
The conversion of electrical energy from a stimulus into a change in membrane potential in a receptor cell.
Receptor potentials/generator potentials
Local changes in membrane potential.
Pacinian corpuscle
A skin receptor that detects vibration. Stimulus to this receptor produces a graded electrical potential. When the potential is big enough, the receptor reaches threshold and generates an action potential.
Coding
Patterns of action potentials in a sensory system that reflect a stimulus.
Range fractionation
This takes place when different cells have different thresholds for firing over a range of stimulus intensities.
Somatosensory system
system that detects body sensations, including touch and pain.
Adaptation
The progressive loss of response to a maintained stimulus.
Tonic receptors
These receptors show slow or no decline in action potential frequency.
Phasic receptors
receptors display adaptation and decrease frequency of action potentials.
Top down processing
when higher brain centers suppress some sensory inputs and amplify other.
Receptive field
the space in which a stimulus will alter a neuron’s firing rate.
Primary somatosensory cortex (S1)
Receives touch information from the opposite side of the body.
Secondary somatosensory cortex (S2)
Cortex that maps both sides of the body in registered overlay.
Polymodal cells
theses cells allow for intersensory interactions.
