CHAPTER 13 PERCEPTUAL DEVELOPMENT AND HUMAN MOVEMENT Carl Gabbard PhD Made by Wang Yan

§13.1 VISUAL PERCEPTION §13.2 KINESTHETIC PERCEPTION §13.3 TACTILE PERCEPTION §13.4 PERCEPTUAL INTEGRATION §13.5 CHANGES WITH ADVANCED AGING §13.6 GIBSON’S ECOLOGICAL PERSPECTIVE §13.7 PERCEPTUAL-MOTOR TRAINING

§13.1 VISUAL PERCEPTION

Developmental Change in Visual Structures  Although all of the visual structures are intact at birth, several are immature in terms of myelinization and synaptic potential.  Development proceeds rapidly - by the end of the first year the major structures of the retina are like those of the adult.

 The part of the nervous system that relays visual impressions between the retina and the cortex of the brain also develops quickly and reaches a large part of its ultimate efficiency during the first year of postnatal life.

Developmental Change in Visual Functions  Visual acuity  Visual acuity refers to clearness of vision and the capacity to detect both small stimuli and small details of large visual patterns.  From a motor behavior perspective visual acuity often is classified as static or dynamic.

 factors that affect visual acuity  development of the fovea  degree of myelinization  number of neural connections in the visual cortex shape  structure of the eye  strength of the ciliary muscles

 Object Permanence  The realization that objects continue to exist when they are no longer in view is object permanence.  This ability is considered one of the more notable achievements in perceptual development.  A-not-B error

 Figure-Ground Perception  It refers to the ability to distinguish an object from its surrounding background  This ability requires the individual to concentrate on and give selective attention to a visual stimulus.

 Depth Perception  It is the ability to judge the distance of an object from the self.  Consists of absolute distance and relative distance.  Oculomotor cues and visual cues  It is generally agreed that depth perception is absent at birth. Most sources indicate that by the age of 6 months, children are capable of judging depth with fair accuracy.

 Field of Vision (peripheral vision )  Field of vision refers to the entire extent of the environment that can be seen without changing the fixation of the eye.  vertical and lateral capabilities  Only after age 5 are visual fields equivalent to those of adults.

 Perception of Movement and Visual- Motor Coordination  One of the most important and complex perceptual abilities related to motor behavior is the detection, tracking, and interception of moving objects.  The ability to coordinate visual abilities with movements of the body is visual- motor coordination.

 eye-hand or eye-foot integration  proximodistal,midline to periphery, cephalocaudal,head to toes, and gross- to-finemotor order.

§ 13.2KINESTHETIC PERCEPTION

 Often referred to as the sixth sense, kinesthetic perception is a comprehensive term that encompasses the awareness of movement and body position.  It based on information that derives from the individual’s internal environment.

 It receives sensory input from receptors located in muscles, tendons, joints, and the vestibular (balance) system.

Development of Kinesthetic Perception  kinesthetic acuity  refers to the ability to detect differences or match qualities such allocation, distance, weight, force, speed, and acceleration.  kinesthetic memory  involve a reproduction of movements

Basic Movement Awareness  body awareness  spatial awareness  directional awareness  vestibular awareness  rhythmic awareness

 Body Awareness  Sometimes referred to as body concept, body knowledge, or body schema  It involves an awareness of body parts by name and location, their relationship to each other, and their capabilities and limitations.

 The knowledge of body parts and their functions is one of the most basic aspects of kinesthesis.  The ability to identify various body parts depends heavily on both conceptual and language abilities, as well as other sensory perceptions.

 Spatial Awareness  It interplays with the visual perception of spatial orientation.  The sense of the location of one’s body in space in relationship to the environment.  Egocentric localization and Objective localization

 Directional Awareness  Directional awareness refers to the conscious internal awareness of two sides of the body (laterality) and the ability to identify various dimensions of external space and project the body within those dimensions (directionality).

 In theoretical terms, directional awareness is that aspect of kinesthetic perception assumed to be an extension of body and spatial awareness.  From a theoretical perspective, directionality is the motoric expression of laterality and the perception of spatial orientation.

 Vestibular Awareness  The successful performance of virtually all motor skills depends on the individual’s ability to establish and maintain equilibrium (balance).  The general description for this component is vestibular （前庭的） awareness.

 Balance is subdivided into three types: postural balance, static balance, and dynamic balance.  Common testing procedures for static balance include standing on one foot and balancing on a stabilometer or balance board.  The assessment of balance at any age is related to the specific task used to measure it.

 Rhythmic (Temporal) Awareness  It refers to creating or maintaining a temporal pattern within a set of movements.  Even young infants seem to be born with the tendency to make rhythmic movements with parts of their bodies.

 It suggest that children between 2 and 5 years of age improve considerably in their ability to keep time to a rhythmical stimulus and that periods of improvement continue to adulthood.  Better accuracy scores were recorded at faster rather than slower tempos.

§13.3 Tactile Perception

Tactile Perception  Tactile perception (touch) refers to the ability to detect and interpret sensory information cutaneously.  In conjunction with kinesthetic perception, often referred to as the tactile-kinesthetic system.

§13.4 PERCEPTUAL INTEGRATION

 The description of developmental characteristics and improvements ‘within’ individual sensory systems is referred to as intrasensory development.  The perceptual and perceptual- motor processes is known as perceptual integration.  Intermodal perception

 Visual-Kinesthetic Integration  Visual-Auditory Integration  Auditory-Kinesthetic Integration

§13.5 CHANGES WITH ADVANCED AGING

Visual Perception  A loss of visual abilities is one of the most noticeable changes in perceptual functioning as the body passes its peak performance level.  Most people begin to notice changes in visual acuity between 40 to 50 years of age.  presbyopia  Sensitivity to light

Kinesthetic Perception  Most of the research on kinesthetic perception is grouped under the heading of somesthetic senses.  People approaching middle age would have diminished somesthetic function.  However, research findings on age differences in somesthetic sensitivity have not provided clear-cut evidence of the parallel.

 Perhaps the most abundant information available about age effects on somesthetic sensitivity is in tactile perception.  The degree of loss varies widely among individuals and differs for various parts of the body.

§13.6 GIBSON’S ECOLOGICAL PERSPECTIVE

 The perceptual theory that has had the greatest impact on our understanding of how infants perceive and act on that information in the form of movement is Gibson’s ecological perspective.  An important characteristic of this theory is the assumption that infants can directly perceive information that exists in the environment.

 According to this perspective, infants actively explore for invariant features of the environment – that is, features that remain stable in a constantly changing perceptual world.

 Central to this notion is the observation that infants constantly explore ways in the environment that afford opportunities for action.  The notion of affordances emphasizes there is an ecological fit between the individual and the situation.

 Overall, the ecological perspective provides us with one idea of how perception and action work, perhaps the most relevant question in the study of motor development.

§13.7 PERCEPTUAL-MOTOR TRAINING

 Some assumption of a strong direct link between perceptual-motor functioning and cognitive (intellectual) functioning.  Most studies have reported little or no relationship among perceptual-motor development, perception, and intellectual performance.

 Perceptual-motor training will improve perceptual-motor functioning.  It is interesting to note that with the recent findings in early brain research and the effects of stimulation on development dramatic claims for training effects have emerged.