Ch. 5 - Sensation and Perception

What are the 5 senses?

-Sound -Smell -Sight -Touch -Taste

Law of closure

A perception experience may be filled in by our brains to be whole- so as to fill in its shape or complete a line

Distinguish between absolute threshold and JND threshold

Absolute threshold is the minimum stimulation needed to notice some other stimulation half of the time. JND threshold is the just noticeable difference, however it differs from absolute threshold because it is the minimum DIFFERENCE in two stimuli that can be detected 50% of the time. For example, the amount of weight it would take for a heavyweight lifter to notice a difference in his weights.

Smell receptor

Olfactory sensory neurons in the olfactory epithelium

Define sensory adaption and explain why it is functional

Over time, our body stops detecting a stimulus, such as a t-shirt we might be wearing. This allows us to be able to focus on any other stimulus shifts or changes in our environment

Contrast sensation and perception

Sensation is the experience that comes from touching, feeling, hearing, smelling, or tasting, and is conducted by your sensory organs. Everyone has sensations, but everyone's perception of those experiences is different. Perception is your conscious experience and views on the world you live in.

Explain how perceptual constancies help us to organize our senses into meaningful perceptions (e.g. shape and size constancy)

These allow us to perceive objects as the same object, even as the lighting or proximity changes. Shape constancy allows us to perceive a door no matter if it is open or closed. Size constancy allows us to perceive objects as the same size, no matter our proximity to the object.

Define perceptual set and explain why the same stimulus can evoke different perceptions in different contexts (i.e. context effects)

They occur when what we expect influences our perception; any stimulus may procure different perceptions based on context; e.g. I3 could be seen as the letter B, or the number thirteen.

Why are illusions helpful

They show how our brains process images and generate perceptions, and reveal that perceptions are governed by comparisons

Describe the Gestalt Psychology's contribution to our understanding of perception and list the 5 Gestalt Principles

This draws on our ability to perceive objects as wholes within their overall context; Closure, Proximity, Similarity, Continuity, and Symmetry.

Taste receptor

chemoreceptors (replaced every 10 days, 4 for each)

Define parallel processing and discuss its role in visual info processing

When our brain processes multiple sets of info, like the image of a bird flapping its wings. Rather than seeing the moving wings in multiple snapshots, we see it as a fluid stream of visuals

Law of continuity

elements of objects tend to be grouped together, and therefore integrated into perceptual wholes if they are aligned within an object

Law of similarity

elements within an assortment of objects are perceptually grouped together if they are similar to each other

Sound receptor

mechanoreceptors (hair cells in cochlea)

Vision receptor

photoreceptors

Describe the process behind our perception of motion (the Phi Phenomenon)

the brain detects motion in a rapid series of slightly different pictures, known as the Phi Phenomenon. Our brain likes to compare current images to past images

Law of symmetry

the mind perceives objects as being symmetrical and forming around a center point

Explain signal-to-noise ratio

the volume of a sound as compared to the volume of background noise

Know how signal detection theory explains the likelihood of perceiving a stimulus

there are four possible outcomes: hit (signal present and subject says "yes"), miss (signal present and subject says "no"), false alarm (signal absent and subject says "yes"), and correct rejection (signal absent and subject says "no"). Hits and correct rejections are good. False alarms and misses are bad.

Touch receptor

thermoreceptors, nociceptors (free nerve endings)

Law of proximity

when an individual perceived an assortment of objects they perceive objects that are close to each other as forming a group

Bottom-up processing

when our Brain perceives a whole image from things like lines, shapes, or colors

Top-down processing

when we analyze and perceive items or events which we've already formed or heard information about, so that we already have expectations of how it should be, which will in turn orient our attention