chapter 5 sensation, perception, and action

sensation

sensation

The process by which sensory receptor neurons detect information and transmit it to the brain

perception

the interpretation of sensory input.

action

Motor activities prompted by sensory and/or perceptual information.

Constructivists

• on the side of nurture:

  • Perceptions are constructed through learning

nativists

• on the side of nature

  • Innate capabilities and maturational programs drive perceptual development.

  • Perception does not require interpretation.

Gibson’s ecological theory of perception

• Nature–nurture are inseparable.

• Proposes that information important for perception is readily and directly available in the environment

• Perception drives action.

• Human learn out of necessity

• Children are information “hunter gatherers”.

Habituation

The same stimulus is repeatedly presented until the infant grows bored with what has become familiar and disengages. Researchers can measure how long until an infant becomes bored. They can measure how distinct a second, new stimulus needs to be in order to recapture the infant’s attention.

Preferential looking

Two stimuli are simultaneously shown to an infant to determine which one they prefer, which is inferred to be the one they look at longer. Adding head-mounted, eye-tracking cameras has allowed researchers to more precisely measure preferential looking.

Evoked potentials

Electrical activity in different parts of the brain is measured while the infant is exposed to stimulation. Electrodes are attached to the surface of the skull and a computer records the pattern of electrical activity corresponding to various stimuli.

Operant conditioning

Infants are conditioned to reliably respond a certain way to a certain stimulus. Once this response is well-established, the researcher can examine the conditions under which the infants will, or will not, continue to produce the behavior.

positive reinforcement

occurs when a behavior (response) is rewarded or the behavior is followed by another stimulus that is rewarding, increasing the frequency of desired behavior. Give a treat is positive reinforcement/if a rat in a Skinner box gets food when it presses a lever, its rate of pressing will go up.

negative reinforcement

occurs when a behavior (response) is followed by the removal of a stimulus, thereby increasing the original behavior's frequency. In the Skinner Box experiment, the aversive stimulus might be a loud noise continuously inside the box; negative reinforcement would happen when the rat presses a lever to turn off the noise. Parent takes away a desired item is negative punishment in order to study or increase a desirable behavior

positive punishment

occurs when a behavior (response) is followed by an aversive stimulus. Example: pain from a spanking, which would often result in a decrease in that behavior. Positive punishment is a confusing term, so the procedure is usually referred to as "punishment".

negative punishment

occurs when a behavior (response) is followed by the removal of a stimulus. Example: taking away a child's toy following an undesired behavior by him/her, which would result in a decrease in the undesirable behavior.

extinction

occurs when a behavior (response) that had previously been reinforced is no longer effective. Example: a rat is first given food many times for pressing a lever, until the experimenter no longer gives out food as a reward. The rat would typically press the lever less often and then stop. The lever pressing would then be said to be "extinguished.“

classical conditioning

• First described by Ivan Pavlov, a Russian physiologist

• Focuses on involuntary, automatic behaviors

• Involves placing a neutral signal before a reflex

operant conditioning

• First described by B. F. Skinner, an American psychologist

• Involves applying reinforcement or punishment to alter or maintain behavior

• Focuses on strengthening or weakening voluntary behaviors

Dynamic Systems Theory

• a theory of motor development

• This theory proposes that movement is produced from the interaction of multiple sub-systems within the person, task and environment.

• A child want to reach their favorite toy/person. Can not go while laying in her/his back but rolling/crawling gets them closer

• Developments take place over time through a “self-organizing” process.

• Children use sensory feedback when trying different movements to modify their motor behavior in adaptive ways.

nativist perspective

• Nativism is the view that certain skills or abilities are "native" or hard-wired into the brain at birth

• When a newborn understands (cries) when parent walk away and a parent walks toward.

• Child learns to call parent/caregiver, beginning to learn words/sounds associated to the environment (parent/toys). Parent walks away-child cries

visual acuity

• Ability to perceive detail

  • At birth, visual acuity is 40 times worse than adult, significant improvements within the first month.

Visual accommodation

Ability of the lens of the eye to change shape to bring objects at different distances into focus

Sense of smell developed at birth

Exposure to familiar smells can calm newborns.

Newborns sensitive to warmth, cold, and pain

• Pain is responsive to learning.

• Breastfeeding during painful events reduce behavioral signs infants are experiencing pain.

Early exposure to auditory stimulation

• Affects the developing brain

• Influences auditory perception skills

locomotion

• Infants acquire gross motor skills before mastering fine motor skills.

• It takes an average of 13 starts and stops over a period of days before toddlers show consistent performance of a motor skill.

Attention

• Focusing of perception and cognition on something in particular

orienting system

• Reacts to events in the environment

focusing system

• Deliberately seeks out and maintains attention to events

Selective attention

• Deliberately concentrating on one thing while ignoring something else

• As children get older, selective attention increases.

General decline in sensitivity to taste

• Men show greater decline than women.

• Middle-aged and older adults have difficulty discriminating among tastes that differ in intensity.

• Do not have difficulty differentiating degrees of sweetness

Ability to perceive odors declines with age

• Can identify and remember unpleasant odors

• Some decline in their ability to detect and remember pleasant odors.