1. Sensory and perceptual development
Chapter 8

2. By the end of this lecture you will
Be familiar with the three components of perceptual development.
Know the main theories of development and how these relate to nature and nurture.
Learn about sensory perception and its important milestones.
Be able to describe intermodal co-ordination.
Know of perceptual-motor programmes which are in common use in many schools.

3. Lecture overview The science of perception.
Sensory and perceptual development.
Intermodal co-ordination.
Perceptual-motor development.
Implications for teaching and learning.

4. Key questions What is sensation?
What are the five main functions of perception?
Is perceptive ability based on the brain hard-wired or based on experience?
How are perception, sensation and action linked?
What is perception and why do we need it?
How does perception develop and what are the ‘milestones’?
What is intermodal co-ordination?
What classroom intervention programmes are available for perceptual development?
What are the implications for teaching and learning of understanding the importance and processes of perceptual development?

5. Sensory and Perceptual Development
What are Sensation and Perception?
Sensation occurs when information interacts with sensory receptors.
Perception is interpretation of what is sensed.
All information comes to the infant through senses; therefore relationship of sensation to perception is crucial for infant as it develops.

6. The science of perception
The components of perceptual development help us gather the information we need to make sense of ourselves and the things that happen to us.
Sensation is the process through which sensory receptors detect information and transmit it to the brain.
Perception is the processes through which we organise and interpret information from the senses.
Cognition is knowing through the formation, memorisation and recall of ideas.
Perception is the bridge between our conscious mind and the external world.

7. Theories of perception
There are two contrasting sets of theories about how perception develops.
The early empiricists (such as Locke) argued that perceptual capacities were constructed out of, and only out of, experience (nurture perspective).
In partial contrast, Piaget’s theory is largely one of reasoning and how children’s cognitive faculties allow them to interpret their sensations.
He describes how children at different stages come to interpret their perceptions, but stresses the interactions between developing cognitive processes and experiences.

8. Theories of perception (Continued)
In greater contrast are nativist views (Kant and Chomsky) which argue that a newborn’s perceptual capacities are already quite advanced and therefore not so dependent upon experience (nature perspective).

9. Theories of Perceptual Development
Constructivist View - states that perception is a cognitive construction based on sensory input plus information retrieved from memory.
Perception, is a representation of the world that builds up as the infant constructs an image of experiences (Piaget, Vygotsky) .
Ecological View - states perception has functional purposes of bringing an organism in contact with the environment and of increasing adaptation (Gibson).

10. Gibson’s theory of perceptual development
Jack Gibson’s ecological theory (1969, 1979, 1988) offers an interactionist approach.
This proposes that a close relationship exists between perception and action.
The interactions of the individual with the environment are important.
These interactions allow vast number of possibilities through their affordances or properties, e.g. a child catching a ball is interacting with the ball and the environment. This provides many different situations and requires different motor solutions.

11. Gibson’s theory of perceptual development (Continued)
It is a development theory because relationships amongst objects provide different information to those who receive it.
Maturation brings about changes in how children perceive.
With increased experiences, children learn to select the crucial elements in their sensory environments and their perceptual capacities become more focused and organised.

12. How much does the development of perception depend on experience?
Eleanor Jack Gibson’s most famous work is the classic ‘visual cliff’ experiment (Gibson & Walk, 1966) which involved the perception of infants, aged 6–14 months.
If babies have no experience of falling, how do they know not to go out over the visual cliff formed by placing clear glass over a drop?
Infants were placed on the centre platform and mothers stood at either end of the platform and called to their children. Nearly all the infants refused to crawl out over the glass on the ‘cliff’ side, but nearly all of them were quite happy to crawl across the glass on the shallow side.

13. How much does the development of perception depend on experience
How much does the development of perception depend on experience? (Continued)
From this study Gibson concluded that depth perception is developed at a very early age.
How much of that development is based on experience and how much on an intuitive dread of going over a ‘cliff’?
Nature or nurture?

14. The contemporary view
Accepts the importance of learning and experience but also affirms how innate processes interact with such experiences.
Accepts that both nature and nurture are involved in perceptual development.
Although experience plays a vital role in perception, it is not the sole basis for creating its capacities.
The range of infant perceptual capacities is much more than previously believed.

15. Research methods
Preference technique – two different stimuli (such as pictures) are presented at the same time to an infant. Researchers measure the time spent by the infant looking at each one. A longer time spent looking at one picture indicates a preference which shows the ability to discriminate.
Habituation – when a stimulus is presented on a number of occasions the child loses interest in it and spends less time looking at it. If the stimulus is changed, the child displays interest in the new stimulus and looks at it for a longer time.
Operant conditioning – teaching an infant to turn her head (learned response); for example, hearing a particular sound when a toy is moving provides reinforcement.

16. Visual Perception Infants can distinguish colours by 2 months of age.
Researchers have also discovered that infants prefer patterns to colors or brightness and faces to shapes.
There is also evidence that infants can perceive depth as their heart rates increase when placed before an illusory precipice.

18. Other Senses
Hearing - Infants certainly can hear but stimulus needs to be louder than that needed for adults, recent research also tells us that foetus can hear and respond to sounds outside the womb.
Touch - Studies completed in 1999 have found that newborn infants do indeed feel pain, which has raised issue with circumcision for boys and caused many parents to rethink their choice on this matter.
Smell - Newborns can differentiate odours, but not at birth.
Taste - may be present before birth and after birth, prefer salty and sweet to sour.

19. The sensory perceptions
Haptic
Touch sense is present at birth but is far from being fully developed.
Touch is vitally important for young children.
Many older children still retain the desire to touch objects.
Touch is a direct means to gain information about the environment and a critical part of cognitive development (Piaget, 1960).
Newborn girls are more sensitive to touch than boys.
Early social handling is important in providing a socio- emotional bond for stimulating intellectual growth and to reduce psychological stress.

20. Gustatory and olfactory perception
The sensory perceptions(Continued)
Gustatory and olfactory perception
Taste and smell perception in the infant are closely related to basic nutritional needs.
Also satisfy a need to interact socially with ‘significant’ others to enhance survival chances.
Both systems provide important sources of exploration and information.
Exposure to different flavours in amniotic fluid and mother’s milk may underlie individual differences in food acceptability (Mennella et al., 2004).
Olfactory discrimination allows infants to show preference for their mother’s breast over those of another lactating mother (Cernoch & Porter, 1985) and is perhaps the first step in mother–child bonding.
Plays a role in alerting to dangers; smells also provide comfort.

21. The sensory perceptions(Continued)
Auditory perception
In the first few days after birth, the infant is capable of hearing, of discriminating sounds and perceiving similarities in sound.
Improvement in perception happens quickly and approaches adult levels for the full range of sounds by two years.
Studies show that infants of four months use environmental clues to locate the source of sounds.
Auditory perception provides a base for language acquisition.

22. The sensory perceptions(Continued)
Visual perception
Visual perception has to be waited for and is underdeveloped at birth.
Visual acuity (the ability to see detail) improves rapidly and from six months is comparable to that of adults (Gwiazda and Birch, 2001).
Colour discrimination improves quickly. By two months infants can discriminate colours across the spectrum.
Depth perception (the ability to judge distances from or to objects) is another aspect of visual perception that infants must master early.

23. The sensory perceptions(Continued)
Visual perception
Newborns prefer to look at patterns rather than dull stimuli and prefer more complex visual patterns as they get older.
Face perception is a special form of pattern perception. Infants prefer looking at complex patterns such as faces.
By three months they prefer human faces with symmetrical features.
Frequent interactions with parents and carers support early social relationships.

24. The sensory perceptions(Continued)
Proprioception
The ‘sense’ that provides information about the position and movement of the body.
Input from this sense is processed through the vestibular system (chiefly concerned with the body’s sense of balance) to keep the body upright and co-ordinate information from the other senses.
It has significant implications for the acquisition of early motor skills such as rolling and crawling and for sitting still or standing still and moving around.
The kinaesthetic sense provides directional and spatial advice.
It also receives input from muscles and tendons and the vestibular system.

25. Intermodal co-ordination
Intermodal perception uses sensory information from more than one sensory modality.
Without the ability to integrate information using different senses, our perceptual capacities would be quite limited.
For example, a two-year-old playing with sand, pouring from one plastic container through the fingers of one hand into another container. This involves proprioception, vision and tactile perception, auditory perception and perhaps taste.
Intermodal matching allows young children to use information from two different sensory modes to detect an object’s distance and direction.
Experimental findings suggest that we may well be born with a capacity to transfer information from one sensory modality to another, and with added experience this capacity increases with age.

26. Perceptual-motor development
A close relationship exists between perception and action.
Motor activity is an immediate way for children to learn about their world and to stimulate their perceptual development.
It can be said with some confidence that motor performance affects perception and the development of perception affects motor performance.
Children with deficits in perceptual performance commonly have difficulties with perceptual-motor tasks.

27. Implications for teaching and learning
A number of recent classroom intervention programmes exist to train the perceptual systems.
Lack of sensory-perceptual development is directly related to observable difficulties in many areas of academic performance.
Kinesiologists argue for the importance of learning through active use of the senses.
Brain Gym is a perceptual-motor programme designed to enhance the experience of whole-brain learning. Inconclusive evidence of influence on academic achievement.

28. Implications for teaching and learning (Continued)
Accelerated learning is a brain-based approach to learning which matches teaching strategies to preferred learning styles: visual, auditory, kinaesthetic. It is commonly used for young children, and children with learning difficulties and sensory impairments.
Handwriting is a good example of where improvements in perceptual motor development can have relatively speedy benefits.