AP Psychology Practice Test: Sensation & Perception

The correct answer is (B). An absolute threshold is the lowest level of a stimulus — light, sound, touch, etc. — detectable by an organism fifty percent of the time.

The correct answer is (B). Neural adaptation or sensory adaptation is a change over time in the responsiveness of the sensory system to a constant stimulus. It is usually experienced as a reduction in responsiveness to the stimulus.

The correct answer is (A). Perception is the process of recognizing, giving meaning to and interpreting sensory stimuli.

The correct answer is (A). Inside of the retina are two types of photoreceptors, rods and cones. Rods are much more sensitive than cones and are adapted for vision in low light. Cones, on the other hand, are adapted for color sensitivity. While there are upwards of 120 million rods in each retina, the cones number 6 to 7 million.

The correct answer is (B). Signals received by the photoreceptor cells (rods and cones) are transmitted to the ganglion cells by way of bipolar cells. More generally, these cells function to transmit sensory information from the site of stimulation to the ganglion cells and then to other brain areas.

The correct answer is (E). Rods are responsible for vision at low light levels. A useful way to remember this difference between rods and cones is that both ‘cones’ and ‘color’ start with a ‘c.’ Cones are mostly used to process colors and rods are mostly used to facilitate vision in the absence of light.

The correct answer is (A). Closure is the perceptual tendency to complete a shape, such as a circle or square, in which a gap in the needed stimulus line currently exists. In the case of a circle with a small portion of its line omitted, “closure” will occur and the small gap will be overlooked and the shape will be perceived as a complete circle.

The correct answer is (B). Gradients of light and shadow create the perceptual phenomenon of bumps and craters; the change following rotation is due to prior knowledge about the most likely source of light (from above).

The correct answer is (D). Interposition refers to the interpretation of depth due to one object covering another. The object being covered appears to be farther away even though the objects could be in the same plane.

The correct answer is (B). Distance perception in a two-dimensional representation of a railroad track is primarily a function of linear perspective. Linear perspective is responsible for the perception of two parallel lines intersecting at a single point.

The correct answer is (E). When an object far in the distance is perceived as a large object instead of its presentation as a small object, size constancy is taking place. In this case, the small object is perceived to be a train due to the surrounding context.

The correct answer is (D). Lights blinking in sequence and perceived as movement are an example of the phi phenomenon. Strobe lights elicit the phi phenomenon.

The correct answer is (C). Specialized receptor cells respond to various external stimuli such as touch, light, temperature, pressure, etc. These receptor cells transduce the physical stimulus into electrical impulses, which, in turn, trigger an impulse in other cells.

The correct answer is (E). In the Japanese language, Umami means savory. The umami receptor on the tongue is activated by glutamate in protein-rich foods.

The correct answer is (D). The difference threshold is the smallest difference that a person can detect between two stimuli. In this case, every tone from 1,100 Hz to 1,149 Hz is perceived as the same.

The correct answer is (B). The kinesthetic sense informs Karen (and all of us) of the position of the limbs. The prefix kin- is Greek for movement, motion, or muscular activity.

The correct answer is (D). The Müller-Lyer illusion is a demonstration of the influence of perspective and context on size perception and is most prevalent in cultures with buildings that have right angles.

The correct answer is (A). The Young-Helmholtz theory of color vision holds that three specialized receptors and there combinations gives rise to the perception of any color.