Sensory and Perceptual Development

Sensory and Perceptual Development

Sensation occurs when the information interacts with sensory receptors- the eyes, ears, tongue, nostrils, and skin. For example, the sensation of hearing occurs when waves of the pulsating air are collected by the outer ear and conducted through the bones of the inner ear and the cochlea, where mechanical vibrations are converted into electrical impulses. Then the electrical impulses move to the auditory nerve, which transmits them to the brain.

Perception is interpretation of sensation. For example, the air waves that contact the ears might be interpreted as noise or as musical sounds. The physical energy transmitted to the retina of the eye might be interpreted as a particular color, pattern, or shape, depending on how it is perceived.

• After the early adult years, visual acuity declines.
• Eye accommodation decreases the most from 40 to 59 years of age.
• In older adults, the yellowing of the eye's lens reduces color differentiation, and the ability to see the periphery of a visual field declines.
• Significant declines in visual functioning related to glare characterize adults 75 years and older and even more so those 85 years and older.
• Three diseases that can impair the vision of older adults are cataracts, glaucoma, and macular degeneration.

The fetus can hear sounds such as the mothers voice and music during the last two months of pregnancy. Immediately after birth newborns can hear, but their sensory threshold is higher than that of adults. Developmental changes in the perception of loudness, pitch, and localization of sound occur during infancy. Most childrens hearing is adequate, but one special concern is otitis media. Hearing can start to decline by the age of 40, espically sensitivy to high-pitched sounds. However, hearing impairment usually doesnt become much of an impediment until late adulthood. Hearing aids can diminish hearing problems for many older adults.

Newborns can respond to touch and feel pain. Sensitivity to pain decreases in late adulthood. Newborns can differentiate odors, and sensitivity to taste is present before birth. Smell and taste may decline in late adulthood, although in healthy individuals the decline is minimal.

What is perception?

Visual Perception

What is Sensation?

The Ecological View

• The infants visual acuity increases dramatically in the first year of life. Infants can distinguish some colors by 8 weeks of age, and possibly by as early as 4 weeks.
• Young infants systematically scan human faces.
• By 3 months of age, infants show size and shape constancy.
• As visual perception develops, infants develop visual expectations.
• In Gibson and Walk's classic study, infants as young as 6 months of age had depth perception.
• Much of vision develops from biological foundations but environmental experiences can contribute to the development of visual perception.
• During the preschool years, children become better at differentiating colors and scanning the visual world.

Other Senses

Created by the Gibsons, the ecological view states that people directly perceive information that exists in the world. Perception brings people in contact with the environment in order to interact with and adapt to it. Affordances provide opportunities for interaction offered by objects that fit within our capabilities to perform activities. Researches have developed a number of methods to assess the infants perception, including the visual preference method (which Frantz used to determine young infants' interest in looking at patterned over nonpatterned displays), habituation and dishabituation, and tracking.

Hearing

Intermodal Perception

Nature/Nurture and Perceptual Development

Crude, exploratory forms of intermodal perception-the ability to relate the intergrate information from two or more sensory modalities-are present in newborns and become sharpened over the first year of life.

THE END!

In perception, nature advocates are referred to as nativists and nurture proponents are called empiricists. The Gibsons' ecological view that has guided much as perceptual development research leans toward a nativist approach but still allows for development changes in distinctive features. Piaget's constructivist view leans toward an empiricist approach, emphasizing that many perceptual accomplishments must await the development of cognitive stages in infancy. A full account of perceptual development includes the roles of nature, nurture, and the developing sensitivity to information.