Sensation and Perception — HS Psychology practice questions

After a few minutes you no longer notice the smell in a room. This is:

1. selective attention
2. perceptual set
3. sensory adaptation
4. the difference threshold

Answer: C — sensory adaptation

C) Correct — Receptors respond less to a constant, unchanging stimulus. A) Is choosing what to focus on. B) Is expectation shaping perception. D) Is the smallest noticeable change.

Sensation differs from perception in that sensation is:

1. the organizing of sensory input into meaning
2. a purely conscious process
3. the detection of physical energy
4. recognizing a familiar face

Answer: C — the detection of physical energy

C) Correct — Receptors detect light, sound and pressure; perception then organizes and interprets that input. A) Is perception. B) Much sensation happens without awareness. D) Is perception, which interprets sensory input.

The vestibular sense tells you about:

1. the position of your limbs
2. pain in internal organs
3. balance and head position
4. sounds detected by the cochlea

Answer: C — balance and head position

C) Correct — The semicircular canals and vestibular sacs in the inner ear track head movement and tilt. A) Is kinesthesis. B) Is detected by other receptors. D) The cochlea handles hearing; it sits beside, but is separate from, the vestibular organs.

Staring at a red image and then at a white wall produces a green afterimage. This supports:

1. opponent-process theory
2. trichromatic theory
3. place theory
4. feature detection

Answer: A — opponent-process theory

A) Correct — Color cells work in opposing pairs (red–green, blue–yellow); fatiguing one side lets the other rebound. B) Explains the three cone types but not afterimages. C) Explains how we hear pitch. D) Explains cells that respond to edges and angles.

Hungry people are quicker to notice food-related words. This is an example of:

1. perceptual set
2. sensory adaptation
3. bottom-up processing
4. the cocktail party effect

Answer: A — perceptual set

A) Correct — Needs and expectations prime us to perceive some things over others. B) Is declining sensitivity to a constant stimulus. C) Is data-driven; this is expectation-driven. D) Is noticing your own name in a noisy room.

Weber's law says that to notice a difference, a stimulus must change by:

1. a fixed amount, whatever its size
2. a constant proportion, not a fixed amount
3. at least half its original size
4. an amount that shrinks as the stimulus grows

Answer: B — a constant proportion, not a fixed amount

B) Correct — The heavier the weight, the more must be added before the change is noticed. A) Reverses Weber's law. C) The proportion depends on the sense and is usually much smaller. D) The needed change grows with the stimulus.

Top-down processing is perception guided by:

1. raw sensory features alone
2. the strength of the physical stimulus
3. reflexes in the spinal cord
4. expectations and prior knowledge

Answer: D — expectations and prior knowledge

D) Correct — We use what we already know to interpret incoming information. A) Is bottom-up processing. B) Affects detection, not how knowledge shapes interpretation. C) Bypass interpretation.

You see a circle with a small gap as a complete circle. This is the Gestalt principle of:

1. proximity
2. similarity
3. figure-ground
4. closure

Answer: D — closure

D) Correct — The brain fills in gaps to perceive whole objects. A) Groups items that are near each other. B) Groups items that look alike. C) Separates an object from its background.

Sensation vs perception?

Sensation: detecting stimulus. Perception: interpreting it.

Gestalt principles?

Whole > sum of parts. Proximity, similarity, closure, continuity, figure-ground.

Difference threshold (JND)?

Just Noticeable Difference. Smallest detectable change.

Absolute threshold?

Smallest stimulus detectable 50% of time.