Chapter 4 & 5 Notes AP Tips

Be prepared to describe how transduction affects the process of sensation and perception.

The sensation process starts with an accessory structure. Lens of eye, outer ear; responsible for collecting and modifying energy from the environment

The next step involves sensory receptors. Specialized cells that respond to certain energy fluctuations in the environment

As sensory receptors detect certain types of energy, the process of transduction begins. Transduction occurs when physical energy is converted into neural code, making it possible for the brain to interpret the energy.

Information from the sensory receptors is transmitted via sensory nerves to the central nervous system.

All of the sensory information, except for smell, is sent to the thalamus. Information is analyzed and relayed to the appropriate area in the cerebral cortex.

The sensory cortex, located in the cerebral cortex, processes the sensory information.

Know factors that affect sensation. Absolute threshold Response criterion Difference threshold Weber’s law Sensory adaptation

Understand how we are able to see. Photoreceptors: rods and cones Accommodation: the process of how the lens focuses in and out on images Ganglion cells: specialized neurons that receive and process information from the receptor cells before the information is sent to the brain Optic nerve: formed from axons of the ganglion cells; carries visual info to the brain

Understand the theories of color vision. Trichromatic theory: there are 3 types of cones, each sensitive to a specific wavelength: red-sensitive (long wavelength), green-sensitive (medium wavelength), blue-sensitive (short wavelength) Opponent-process theory: color-sensitive components of the eye are grouped into three pairs: red-green, blue-yellow, and black-white. Each member inhibits or opposes the other.

Know how each part of the ear contributes to audition. chart

Theories of audition Frequency-matching theory: vibrations of the basilar membrane are determined by the frequency of the vibration. Place theory: pitch depends on where vibrations stimulate the basilar membrane.

Understand how we are able to smell things. Smell is the only sense that does not first send information to the thalamus. Sense of smell is referred to as olfaction Olfactory nerves Olfactory bulb

Understand how we area able to taste things. Taste buds are sensory receptors that are activated when substances enter the mouth Five types of taste buds: sweet, salty, sour, bitter and umami (“meaty” foods)

Understand how people experience pain and what factors contribute to increased or decreased pain perception. Gate-control theory: pain is determined by the opening and closing of neurological gates in the spinal cord Endorphins are released in response to pain

Understand the difference between bottom- up and top-down processing Bottom-up: the organization of information, without the use of prior knowledge Top-down: the organization of information that uses prior knowledge to form the whole Puzzle example

Be familiar with Gestalt Laws “laws” regarding perceptual organization chart

Understand monocular & binocular cues Primarily responsible for depth perception Perceived from one eye Chart Binocular cues: images that are perceived by both eyes and allow for accurate detection of depth perception

Know perception terms Perceptual constancy: ability to see an object as maintaining its original shape, color, brightness, or size as change occurs Stroboscopic motion: the perception of movement due to the rapid presentation of changing stationary images Phi phenomenon: apparent movement due to the sequential presentation of stationary images