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Visual-Spatial Skills
Spatial thinking refers to the connection or relationship between points in space, which can be between an object and oneself or between two or more objects outside of oneself. These associations are referred to as spatial relations. This includes knowing how near or far, high or low, tall or short, thin or wide, straight or bent, close together or far apart objects are to the self and to other objects. Spatial relations though don't just refer to qualities such as size and distance but also relate to volume, order and time. Examples of spatial relationships includes recognising the order of letters in a word. It’s knowing how to space written work or keeping to the line. It’s being able to complete a task in a set period of time. Spatial thinking or knowledge of what is outside of ourselves begins developing soon after birth. We develop an internal awareness of our body parts in relation to each other, and to our surroundings. In other words we learn where our arms, legs and trunk are situated in relation to each other. By waving and spreading its arms a baby learns how wide it is, by kicking its legs it learns how long it is. This process of perceiving body parts and their relations is known as body awareness. It is through these movements that the child develops an understanding of their own visual space. As the child progresses to the toddler stage they learn to move around and experience the space around them. Effectively they construct an inner map of their world and their position in it. They learn to understand how objects occupy space and to understand the size of objects in relation to their bodies. We effectively use our bodies as a measurement device. How high is the chair? Do I need to duck my head when I walk under the kitchen table? These perceptions occur through movement, touch, balance, vision and hearing, which allows the child to learn the nature of form and of boundaries in space. For example when a baby crawls their arms tell their eyes how far the floor is away. By using this distance as a fixed reference they can then estimate how far other objects are from them. ie. How far is that toy will I need to make an extra effort to reach for it? Researchers believe that crawling is essential to developing eye hand co-ordination. Interestingly the distance to the floor when crawling is the same as our reading distance, therefore early crawling experience is essential at preparing our focus and eye co-ordination for reading. Children who do not crawl or crawl inefficiently (ie. bumshufflers and commando crawlers) often have delays in the development of their eye hand co-ordination. Balance is crucial to the development of spatial awareness since it supplies the brain with information about the body's position in space. This information gives the child a sense of centre in space or gravitational security. Knowledge of one's position in space is essential for directional awareness. As the child continues to explore their environment they learn to organise their visual space and begin to understand directions on themselves which is known as laterality. ie. The right hand is on the opposite side of the body to our left hand. This awareness develops simultaneously with the maturation of the central nervous system in which each side of the brain becomes specialised in its function. A child must understand direction on themselves before it can be applied in space. If a child cannot tell their right side from their left, they cannot be expected to judge the direction of one object in relation to another since we always learn to judge where things are by first learning how to relate it to ourselves. As development continues they learn to understand that spatial relations though don’t just refer to relationships to ourselves but can be between two or more objects outside of oneself, which is known as directionality. Directionality is the ability to judge the orientation and position (ie. right and left) of objects relative to oneself and relative to other objects. To an infant an object looks the same no matter which way it faces. For example they learn to point to a chair and name it as a chair, if the chair falls over or is turned around they know that it is still called a chair. In other words we have taught them to name objects in terms of their shape and to disregard the direction in which the object faces. Similarly, to a four-year-old the left shoe appears exactly the same as the right, which is why children have a tendency to place the wrong shoe on the wrong foot. Learning numbers and letters is one of the first occasions in a child’s life that the direction of objects is important. When the letter 'p' points to the left, it’s a 'q', and when a 'd' points to the right, it’s a 'b'. Many children in the early grades of school often have poor awareness of direction especially right and left. Right and left awareness should be as innate as ‘up’ and ‘down’ directions. We are unequivocally aware that ‘up’ is ‘up’ and ‘down’ is ‘down’ in a similar way we need to develop the same concrete awareness of right and left. A child with poor directional and spatial concepts will have difficulty in the classroom. When reading and writing we must always begin on the left and work toward the right. The child may have difficulty knowing where to begin writing on a piece of paper. Their writing may appear disorganised. Words may be widely spaced or tightly pushed together. They may write everything as one very long sentence. The child may have difficulty organising columns of numbers and margins are often ignored. Children with directional problems will commonly reverse letters in words. A child may confuse ‘b’ with ‘d’, ‘was’ with ‘saw’, ‘on’ with ‘no’, but not all the time. What these children have is an instability of form. These children will often capitalise certain letters such as ‘b’ and ‘d’ when writing to circumvent this inconstancy. In fact many practitioners believe that children should be taught capital letters before lower case letters since capital 'B, D, P and Q' all have different distinctive shapes unlike their lower case counterparts. Visual-spatial skills should be well developed by 7-8 years of age. Studies[i] [ii] have shown that below average readers make significantly more reversal errors than above average readers and that the persistence of reversals beyond third grade is a reliable predictor of reading achievement. Thus tests of visual-spatial processing are accurate indicators of reading performance [iv]. Reading text has a very high spatial demand or load. Reading requires the child to fixate the word being read whilst maintaining spatial awareness of the next phrase or line where attention is to be directed. The subsequent eye movement needs to be fast and accurate to ensure the child doesn't lose their place. Consequently spatial awareness and eye tracking are closely related. Efficient eye movement skills are essential in developing good directionality, since how we scan a letter is important when coding it to the brain. Impaired visual-spatial awareness directly impacts on eye movement control. Good readers have a left to right directional tracking preference, whereas poor readers (such as dyslexics) do not show a directional tracking preference due to poorly developed laterality [iii]. Children need to be taught to track in a left to right direction, which helps explain why some children’s writing is disorganized when they copy from the board since they may be tracking across the board from right to left, up and down, or even diagonally.
Many children with learning difficulties have problems making the
necessary scanning eye movements when analysing a visual scene, whether
it be numbers, letters, words, graphs or diagrams. In fact they may try
to analyse the scene without making any eye movements at all, which
makes their judgements horribly inaccurate.
The above pictures highlights the difficulty children with spatial difficulties face. The picture on the right is intended to be an exact reproduction of the picture on the left. The picture belongs to a 5 year old boy with dyslexia. He cannot accurately reproduce a geometric form consisting of two lines. Consequently he would be unable to recognise or copy most letters and numbers containing two or more lines. ie. The number '4' consists of three separate lines and the letter 'w' has four. Many children have difficulty recognising diagonal forms, again many letters and numbers contain diagonal lines such as 'k, v, w, x, y, z' and the numbers '2, 4, 7'. Spatial awareness also relates to sequencing and time; and is fundamental to reasoning and to understanding language. For example, words such as ‘first’ & ‘last’, ‘next’ & ‘previous’, ‘yesterday’ & ‘tomorrow’, ‘over’ &’ under’, ‘through’, ‘towards’ and ‘away from’ lack meaning to a child who has problems with visual spatial relations. Our language makes a fundamental distinction between nouns (describing words) and verbs (doing words). Nouns divide the world into categories of objects whereas verbs (also prepositions and propositions) break things down very differently to nouns, singling out relations between the objects. When referring to spatial concepts we use what are called trajectors and landmarks. The trajector is the thing being related and the landmark is the thing being related to. The choice of trajectory and landmark are important, for example the bike is to the right of the car is different to the car is to the right of the bike. Spatial awareness is crucial in understanding punctuation which after all is putting the spaces of oral language in written form. If a child doesn’t appreciate these pauses in oral language they are unlikely to see the need for commas and spaces between words when writing. Children with spatial difficulties often have problems with social interaction. They are often unaware of the space their body occupies therefore may appear to bump into other people and invade their personal space. They often experience anxiety in new surroundings due to their spatial uncertainty therefore they may prefer familiar or repetitive environments and activities. They may also have difficulty following out sequenced instructions in correct order. The following figure demonstrates the importance of spatial perception upon social skills. The mood of the figure on the left is visibly poorer than that on the right. Spatial changes in posture and facial expression are critical markers of mood. Unfortunately many children particularly those who are Autistic are unable to recognise these often subtle physical signs.
[i] [ii] Patton JE, Yarbrough DB, Thursby D. Another look at children's symbol reversals. Percept Mot Skills 2000 Apr;90(2):577-8. [iii] Hermann HT, Sonnabend NL, Zeevi YY. Interhemispheric coordination is compromised in subjects with developmental dyslexia. Cortex 1986 Sep;22(3):337-58. [iv] Larter S; Naduvilath TJ. Spatial Load Factor as a predictor of reading performance. Journal of Behavioural Optometry. Vol 17 No5. 2006.
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