Lecture 23 Flashcards
What are the types of input into the CNS?
special senses such as vision, hearing, taste, smell and pheromones and vestibular (balance)
somatic and visceral sensations: touch, pain, warm and cold, body position/ proprioseption
What are other ways to get information into the brain?
Direct through the hypothalamus and endocrine which is food intake regulation
What is the sensory receptors
Sensory ending of an afferent neuron or a specialised receptor cell
What does modality mean?
Highly sensitive to a particular stimulus
What are the 4 types of information that describe a sensory stimulus?
Modality, intensity, duration and location.
What is location in terms of a sensory stimulus?
Location of a sensory receptor activated, mapped in the brain
What is intensity in terms of a sensory stimulus?
Frequency of action potential firing in afferent neuron
What is duration in terms of a sensory stimulus?
Duration of action potential firing in afferent neuron
What do you need to act at all times on a muscle spindle?
Tension
What are sensory receptors most sensitive to?
Change
What do sensory receptors often show?
Adaptation, decreased output over time in response to continuous stimulation
Define receptive field
Region of space in which a stimulus can lead to activity in a particular afferent neuron
What gives a good discrimination in receptive fields?
Small fields and dense innervation gives good discrimination.
What is transduction?
Sensory stimulus converted into action potentials
Describe sensation
Conscious identification of what and where, it is the primary region of cortex
