Sensory Physiology

Question 1

Sensory Perception

Answer 1

Stimuli → impulse → brain

Question 2

Perception

Answer 2

Conscious interpretation of the external world

Question 3

Receptor Physiology

Answer 3

-Sensory receptors

• Function
• Law of specific nerve energies
• Classes

Question 4

Sensory Receptor function

Answer 4

Detect specific modalities from environment → impulse
Modality: energy forms
Ex: photons, chemicals, sound waves, pressure, temperature

Question 5

Law of specific nerve energies

Answer 5

Each receptor is specific for a particular modality

→ adequate stimulus: modality that receptor responds best to

Question 6

Classes

Answer 6

Photoreceptors
Chemoreceptors
Thermoreceptors
Mechanoreceptors

Question 7

Sensory Transduction

Answer 7

Stimulus energy → receptor potential
Receptor potential:
Graded potential
Formed by opening/ closing ion channels on receptor membranes
If threshold is met → AP

Question 8

Receptor forms

Answer 8

Modified end of sensory neuron
Ex: ordorant receptors of a cell
Sensory cell that can respond to an adequate stimulus → NT → sensory neuron
Ex: hearing, vision, taste

Question 9

Sensory Unit

Answer 9

Single afferent neuron and all its receptors
Receptors: all the same type
Receptive field: area where an adequate stimulus can produce a response
Activation of multiple receptors → AP

Question 10

Sensory pathways

Answer 10

Information from receptors → neurons → sensory cortex
Neurons
Afferent (first order neuron): PNS → CNS
2nd order neuron: spinal cord or brainstem → thalamus
Third order neuron: thalamus → cortex
When reaches sensory cortex → perception