102,807
edits
Changes
From Nordan Symposia
Jump to navigationJump to search→Smell, Taste, and Touch
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===
[[Image:Smell,_taste,_touch.jpg|right|frame]]
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.
