Changes

'''Sensations''' are units of [[information]] received from the [[environment]], such as a visual feature or a [[sound]]. [[Perceptions]] are organized and interpreted sensations, such as recognizing a face or interpreting a sequence of sounds as a familiar song. These [[concepts]] represent more of a historical distinction than a functional distinction; nevertheless, the distinction between sensation and perception continues to be made by [[research]]ers and textbook writers. Perceptual development is the emerging capacity to detect information from the environment and from internal sources to adapt to and function within the world. [[Knowledge]] about the perceptual development of infants has expanded more rapidly than that of older children. This discrepancy has occurred because the earliest appearance of various perceptual capacities has been emphasized. In addition, knowledge about visual development has expanded more rapidly than knowledge about the development of other perceptual systems. This discrepancy has occurred, in part, because of the [[belief]] that the visual system provides the best source of external information.

'''Sensations''' are units of [[information]] received from the [[environment]], such as a visual feature or a [[sound]]. [[Perceptions]] are organized and interpreted sensations, such as recognizing a face or interpreting a sequence of sounds as a familiar song. These [[concepts]] represent more of a historical distinction than a functional distinction; nevertheless, the distinction between sensation and perception continues to be made by [[research]]ers and textbook writers. Perceptual development is the emerging capacity to detect information from the environment and from internal sources to adapt to and function within the world. [[Knowledge]] about the perceptual development of infants has expanded more rapidly than that of older children. This discrepancy has occurred because the earliest appearance of various perceptual capacities has been emphasized. In addition, knowledge about visual development has expanded more rapidly than knowledge about the development of other perceptual systems. This discrepancy has occurred, in part, because of the [[belief]] that the visual system provides the best source of external information.

==Educational Psychology==

==Educational Psychology==

In [[education]]al [[psychology]], a quick review of several introductory textbooks reveals that little attention is given to sensation and perception. Most textbooks mention information processing theories of knowledge acquisition and include a three component model of [[human]] [[memory]] consisting of sensory registers, short-term working memory, and long-term memory. Within this [[model]], the sensory registers receive environmental input. These registers have a large capacity to receive information, but the information quickly fades away unless it is transferred to short-term working memory. The other section of educational psychology textbooks in which sensations and perceptions are mentioned concerns students with special needs, in particular, those with a sensory challenge such as a visual or auditory impairment. Despite this limited coverage, much knowledge has been obtained on perceptual development within the last half-century and a familiarity with this knowledge could facilitate the teaching of students.

In [[education]]al [[psychology]], a quick review of several introductory textbooks reveals that little attention is given to sensation and perception. Most textbooks mention information processing theories of knowledge acquisition and include a three component model of [[human]] [[memory]] consisting of sensory registers, short-term working memory, and long-term memory. Within this [[model]], the sensory registers receive environmental input. These registers have a large capacity to receive information, but the information quickly fades away unless it is transferred to short-term working memory. The other section of educational psychology textbooks in which sensations and perceptions are mentioned concerns students with special needs, in particular, those with a sensory challenge such as a visual or auditory impairment. Despite this limited coverage, much knowledge has been obtained on perceptual development within the last half-century and a familiarity with this knowledge could facilitate the teaching of students.

==Development of Individual Senses==

==Development of Individual Senses==

===Vision===

===Vision===

In 1890, [[William James]] described the newborn infant's visual world as a blooming buzzing confusion. This view represents a strong [[empiricist]] [[perspective]] that perception develops through learning. It is now known that the newborn's view of the world is not this confusing and also that many important perceptual developments occur within the first year of life. Some principles of looking in infancy include opening the eyes when the [[light]] is not too bright, making broad eye movements until an edge (an area of high contrast) is found, and then continuing to look in the general vicinity of the edge (while making eye movements across the edge). These principles maximize the firing rate of [[neurons]] in the [[eye]] and [[brain]], which may facilitate further visual developments. Several functions of vision are presented in the following paragraphs, including kinds of eye movements, pattern detection, image features, and depth perception.

In 1890, [[William James]] described the newborn infant's visual world as a blooming buzzing confusion. This view represents a strong [[empiricist]] [[perspective]] that perception develops through learning. It is now known that the newborn's view of the world is not this confusing and also that many important perceptual developments occur within the first year of life. Some principles of looking in infancy include opening the eyes when the [[light]] is not too bright, making broad eye movements until an edge (an area of high contrast) is found, and then continuing to look in the general vicinity of the edge (while making eye movements across the edge). These principles maximize the firing rate of [[neurons]] in the [[eye]] and [[brain]], which may facilitate further visual developments. Several functions of vision are presented in the following paragraphs, including kinds of eye movements, pattern detection, image features, and depth perception.

Despite the rapid development of the visual system during infancy as indicated in several capabilities, visual perception continues to develop and become more efficient throughout childhood. For example, visual skills become better focused, better organized, and more confined to meaningful environmental features as children age.

Despite the rapid development of the visual system during infancy as indicated in several capabilities, visual perception continues to develop and become more efficient throughout childhood. For example, visual skills become better focused, better organized, and more confined to meaningful environmental features as children age.

===Audition===

===Audition===

Like the visual system, the auditory system is also functional at birth and is fast developing. Fetuses hear before birth: They react to [[sounds]] by moving around, and their [[heart]] rate increases. Newborns recognize stories that their mothers repeatedly read out loud before they were born, and they prefer to listen to their mothers' [[voice]]s over those of stranger. Newborns also prefer infant-directed [[speech]] over adult-directed speech. Infant-directed speech (motherese, parentese) is high in [[pitch]], is slow, and has exaggerated rises and falls. This speech may help infants with [[language]] acquisition by directing their attention to particular [[words]].

Like the visual system, the auditory system is also functional at birth and is fast developing. Fetuses hear before birth: They react to [[sounds]] by moving around, and their [[heart]] rate increases. Newborns recognize stories that their mothers repeatedly read out loud before they were born, and they prefer to listen to their mothers' [[voice]]s over those of stranger. Newborns also prefer infant-directed [[speech]] over adult-directed speech. Infant-directed speech (motherese, parentese) is high in [[pitch]], is slow, and has exaggerated rises and falls. This speech may help infants with [[language]] acquisition by directing their attention to particular [[words]].

Auditory perception continues to develop during childhood. For example, the ability to detect low-frequency tones develops over several years.

Auditory perception continues to develop during childhood. For example, the ability to detect low-frequency tones develops over several years.

===Smell, Taste, and Touch===

===Smell, Taste, and Touch===

Researchers have given less attention to the senses of smell, taste, and touch than they have to vision and hearing. These senses are functional early on, and they may be adaptive to the survival of the infant. For example, within the first week of life babies recognize and turn to the smell of their own mother's breast pad over that of another woman. Infants also prefer familiar [[odor]]s over ones to which they have not previously been exposed. Newborns also discriminate among different tastes: They will suck on a sweet solution longer than on sour, salty, or bitter solutions. The sense of [[touch]] contains many types of receptors, including ones sensitive to pressure, pain, and temperature. Even the fetus responds to touch, and the newborn is sensitive to pain, for example, by crying following a pin prick. Other aspects of haptic perception such as the detection of shape, [[texture]], hardness, volume, and weight have been found to be functional within the first one to two years of life.

Researchers have given less attention to the senses of smell, taste, and touch than they have to vision and hearing. These senses are functional early on, and they may be adaptive to the survival of the infant. For example, within the first week of life babies recognize and turn to the smell of their own mother's breast pad over that of another woman. Infants also prefer familiar [[odor]]s over ones to which they have not previously been exposed. Newborns also discriminate among different tastes: They will suck on a sweet solution longer than on sour, salty, or bitter solutions. The sense of [[touch]] contains many types of receptors, including ones sensitive to pressure, pain, and temperature. Even the fetus responds to touch, and the newborn is sensitive to pain, for example, by crying following a pin prick. Other aspects of haptic perception such as the detection of shape, [[texture]], hardness, volume, and weight have been found to be functional within the first one to two years of life.

==Internal Senses: Orienting and Proprioception==

==Internal Senses: Orienting and Proprioception==

There are other sensory systems besides the'' five classic senses'' used for detecting external environmental [[information]]. The orienting system is the sensory [[system]] that allows a [[person]] to detect the position and motion of the [[body]] in [[space]]. The vestibular organs, consisting of the saccule, the utricle, and the semicircular canals, are primarily responsible for this sense. The orienting system is used to register linear and rotary acceleration. It is also used to sense [[gravity]]. Certain types of eye movements show that the vestibular system is functioning. For example, when an individual is rotated, the resulting stimulation of the semicircular canals creates a pattern of eye movements such that the eyes move slowly in the direction opposite of the rotation and then rapidly back. These eye movements are called vestibular nystagmus, and they are easily observable in the newborn infant. With respect to [[gravity]], one interpretation of the frequently observed [[behavior]] of infants systematically dropping objects and watching them fall is that it is helping them learn about gravity. Also, the sense of gravity is so strong among 2-year-olds that they search directly under the location where a ball was dropped even in the [[presence]] of an opaque tube carrying the ball to a different location. In other words, 2-year-olds do not attend to the local information of the tube; instead they use general information about gravity to attempt to solve these problems.

There are other sensory systems besides the'' five classic senses'' used for detecting external environmental [[information]]. The orienting system is the sensory [[system]] that allows a [[person]] to detect the position and motion of the [[body]] in [[space]]. The vestibular organs, consisting of the saccule, the utricle, and the semicircular canals, are primarily responsible for this sense. The orienting system is used to register linear and rotary acceleration. It is also used to sense [[gravity]]. Certain types of eye movements show that the vestibular system is functioning. For example, when an individual is rotated, the resulting stimulation of the semicircular canals creates a pattern of eye movements such that the eyes move slowly in the direction opposite of the rotation and then rapidly back. These eye movements are called vestibular nystagmus, and they are easily observable in the newborn infant. With respect to [[gravity]], one interpretation of the frequently observed [[behavior]] of infants systematically dropping objects and watching them fall is that it is helping them learn about gravity. Also, the sense of gravity is so strong among 2-year-olds that they search directly under the location where a ball was dropped even in the [[presence]] of an opaque tube carrying the ball to a different location. In other words, 2-year-olds do not attend to the local information of the tube; instead they use general information about gravity to attempt to solve these problems.

Michael E. McCarty

Michael E. McCarty

==See also==

==See also==