Special Senses

What are the steps of sensory reception?

Reception, Transduction, Encoding and Transmission, Perception

What is Reception in sensory perception?

Detection of a stimulus by a sensory receptor

What is Transduction in sensory perception?

Conversion of a stimulus into an electrical signal (graded potential)

What is Encoding and Transmission in sensory perception?

Generation and propagation of action potentials along sensory neurons

What is Perception in sensory reception?

Interpretation of the sensation in the CNS; can vary between individuals (e.g., optical illusions)

How does the sense of smell occur?

Molecules bind to chemoreceptors in the nasal cavity, stimulating neurons that generate action potentials; signals sent via olfactory nerves

Why can we not smell some molecules?

We lack chemoreceptors for those molecules

How does the sense of taste occur?

Tastant molecules dissolve in saliva, bind to receptors on gustatory hairs in taste buds on papillae, generating action potentials

What factors affect sense of taste?

Density of taste buds, concentration of tastants, and receptor activation

Which receptors are involved in taste?

Chemoreceptors (taste), Thermoreceptors (temperature of food), Mechanoreceptors (texture), Nociceptors (pain from hot/spicy food)

What is the difference between sensation and perception in hearing?

Sensation = sensory fiber responds to stimulus with action potentials; Perception = brain interprets the information

What is the role of the vestibular apparatus?

Responsible for balance and equilibrium, detects acceleration, deceleration, and orientation with respect to gravity

Outline the pathway of light in the human eye.

Light passes through cornea → lens → retina → optic nerve → optic chiasm → optic tracts → brain

Which side of the brain processes light from the right visual field?

Left hemisphere

What is the function of rods in the retina?

Detect low light levels; responsible for night and peripheral vision

What is the function of cones in the retina?

Detect color (blue, green, red) and high-acuity vision in bright light