Transduction occurs when sensations are perceived. In the case of touch, our fingers detect pressure which is translated into a neural impulse, causing our brain to perceive that we have made contact with a surface.

Proximity, closure, similarity, and continuity are four of the Gesalt rules for perception, whereas difference (the opposite of similarity) is not. Proximity states that groups of objects close together are likely to be grouped together, closure is the tendency to fill in the gaps in a visual scene, similarity describes how objects that look similar are likely to be grouped together, and continuity states that objects with similar orientations are likely to be grouped together.

Figure-ground is one tool our brains use to form perception. This is the organization of the visual field by separating an object (figure) from its surroundings (ground). In this scenario, the apple stands out from the grapes it's surrounded by; therefore, this would make the apple the figure and the grapes the ground. Another example would be a lead singer versus the rest of a band. The lead singer stands out as a separate object, making this individual the figure. The rest of the band would be considered the ground relative to the lead singer.

Binocular cues are depth cues that require the use of two eyes. For instance, trying to touch the tip of two pencils together in front of your face may be rather easy to do with both eyes open; however, attempting this task with one eye open is significantly challenging. Retinal disparity is a binocular cue used to perceive depth between two near objects. It does so by comparing the different images from both retinas. Each eye receives different images because they are usually around two and half inches apart. The greater the difference (disparity) there is between the images, then the closer the object will be. The other options would be incorrect because they are defined as monocular cues. 

Color constancy is when a familiar object may be perceived as having a consistent color regardless of the changing wavelengths reflecting off its surface. It may be an abstract idea for some, but it's important to remember that an object does not contain color itself. Instead, we perceive objects as certain colors because of the wavelengths they reflect. In terms of color constancy, our brains are able to recognize the same color despite different illuminations by taking into consideration the light reflecting off the object relative the objects surrounding it.

Weber's Law states that a change in stimulus that is barely noticeable for a particular person will be a constant ratio of the original stimulus. For a 10-pound weight, the man would start noticing a change when 0.5 pounds was added. Anything less than that, he would not notice. For a 100-pound weight, the man would not notice a 0.5-pound weight change; rather, he would notice a 5-pound weight change since this is the same proportion as observed in the original situation.

The cocktail party effect primarily applies to auditory stimuli, and Gestalt perceptual laws would not explain how one finds an object among lots of similar objects. Top-down processing begins with your knowledge about the situation, which you apply to the current context and use to guide your ability to correctly identify the flamboyant figure. That is, you first remember you are looking for—the figure—and then try to locate a stimulus you can identify as being flamboyant. Bottom-up processing begins with the sensations you experience, which are passed “up” from your retina—via vision—to higher and higher brain areas that can carry out more and more complex analysis. 

Sensation is best understood as simply the stimulation of sensory organs (in this case sight). Perception has to do with selecting, organizing, and interpreting sensory input in a meaningful way. One can sense the features of a stop sign; however, in order to perceive what a stop sign is, one must interpret what the sensory input means. The visual cortex is the portion of the brain that is most likely to process visual stimuli. Learning might be involved in perception; however, the best answer is "sensation. . . perception."

The trichromatic theory is the oldest theory to explain why and how humans see color. It posits that there are three types of cone receptors in the retina, one type for each of the primary colors (e.g. red, blue, and yellow). 

“Retinal disparity” is a binocular depth cue, not a monocular cue. The other answers—relative size cue, texture gradient, and linear perspective—are all monocular cues.