Introduction to the Senses Flashcards
What are the five special senses?
Vision, Hearing, Equilibrium, Taste, Smell
What are the four somatic senses?
Touch, Temperature, Proprioception, Nociception (Pain and Itch)
What do sensory receptors do?
Convert stimuli (e.g., light, sound) into electrical signals.
What is transduction?
The conversion of stimulus energy into a graded change in membrane potential.
What is a receptor potential?
A graded change in membrane potential in response to a stimulus.
What is an adequate stimulus?
The form of energy to which a receptor cell is most responsive.
What are the four types of receptors based on adequate stimuli?
Chemoreceptors, Mechanoreceptors, Thermoreceptors, Photoreceptors
What is the perceptual threshold and what is an example of this?
The weakest stimulus that causes a conscious perception (e.g., ~40 odorant molecules for smell).
What is a receptor threshold?
The weakest stimulus that will cause a response in the receptor.
What are primary sensory neurons and what do they do?
The first neurons in the sensory system that synapse onto secondary sensory neurons.
How do sensory systems indicate modality?
Labelled lines reveal the modality by which axons carry the signal.
What is population coding?
Representing stimulus intensity by the number of active neurons.
How do receptors and neurons respond to changes over time?
They signal changes in stimuli rather than steady levels.
What is frequency coding?
Representing stimulus intensity by the firing rate of individual neurons.
What are phasic cells?
Cells that respond briefly to changes and then stop firing.
