HN220 Lecture Notes - Lecture 4: Medulla Oblongata, Cerebral Cortex, Sensory Neuroscience
Document Summary
Involves precise identification & location of the stimulus. For a sensation to arise, four events typically occur: stimulation. If the receptor potential reaches threshold value, one or more nerve impulses will be propagated by a sensory (afferent) neuron to the cns: note that a given sensory neuron carries only one modality, integration. Integration of the sensory impulses in a specific region of the cns. In the process of integration all of the characteristics of the sensation are conveyed by the pattern of nerve impulses. Photoreceptors in the eye: phasic receptors are normally inactive but become active for a short duration when there is a stimulus, these are quickly adapting and attuned to changing conditions, ex. Interoceptors or visceroceptors are located in the walls of blood vessels and visceral organs and provide information about the internal environment; these sensations often do not reach conscious perception.
