Lecture 6 Sensation & perception

Question 1

What is Sensation and Perception? How do they differ from each other?

Answer 1

Sensation: Senses we receive from the world → electric signals (AP)

Perception: our brain understanding those electric signals (AP) → perception of the world

Distinct thing that work together

Question 2

What is transduction?

Answer 2

process of converting sensory stimulus → action potential (so brain can understand)

Order:
1. Stimuli (world)
2. activate sensory receptor
3. receptors send signal
4. signal changes membrane potentials

Question 3

What are sensory modalities

Answer 3

receptors that perform transduction

ex: (touch, vision, hearing, smell, thermal, pain, balance, proprioception)

Question 4

How is transduction applied to sensory modalities?

Answer 4

The process of transduction is found in various sensory modalities in our body.

→ Both roles allow us to receive stimulus from the world that our brain can interpret, which our body can then respond to

Question 5

Adequate stimulus

Answer 5

• specific type of stimulus that organs respond to
• sensory systems have a restricted range of responsiveness

ex: hearing frequencies across animals/humans

Question 6

Generator Potential or Receptor Potential

Answer 6

• graded
• local potential in membranes when a sensory receptor is stimulated
• depending on the size, it can trigger an AP if threshold is met

Question 7

What is the difference between an GP and AP?

Answer 7

• Generator potential is a precursor for an AP to fire (if threshold is met).
• GP is graded unlike AP’s all or nothing response (same size once fired)
• Both work together in sequence.

Question 8

How does the brain distinguish between different stimuli (from sensory receptors) when all AP’s use the same signalling process?

Answer 8

• Labeled Lines: Brain recognizes distinct signals → different nerve tracts
• Thalamus also helps decide where signal goes

Question 9

Divergence

Answer 9

One neuron (with one signal) → connects to many outputs/neurons

• spreads info and signals serve many purposes

Question 10

Convergence

Answer 10

Multiple neurons (with many signals) → connect to a single output/ neuron

• combines info

Question 11

What is Psychophysics?

Answer 11

It investigates the relationships between physical stimuli (world) and an individuals sensation and perception to it