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Attention Problems

education



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Attention Problems



Attention deviations, like inadequate motivation, interfere with an individual's ability to learn. As described in Chapter 1, in the section on criteria for diagnoses, the presence of an apparent sensory deficit is one of the first indicators that a child's development is not preceding normally. In fact, many consider attention problems to be the main reason for the individual's failure to develop typically.

Itard, the first scientist-practitioner to study a child with severe developmental delays (Victor), considered deficits in sensory processes to be a main cause of Victor's delayed development. To help Victor develop more competent and appropriate behaviours, Itard placed a major emphasis on stimulating Victor's various sensory organs with the hope of opening them to normal receptions. He attempted to accomplish this by engaging Victor in bodily movements, stroking him, and exposing him to fearful situations, hot and cold sensations, electric stimulation of the skin, and a variety of other forms of stimulation. Many of Itard's interventions are still used some 200 years later, and a large range of similar interventions have been tried, all of them designed to alter sensory processing. Such interventions include Sensory-Motor Training, Auditory Integration, stroking with feathers, rubbing with sponges, squeeze machines, and placement in rotating chairs. Sadly, all of these interventions have failed to demonstrate effectiveness in increasing attention and learning (see Chapter 3). One of the more recent developments postulates that a defect exists not in processing one sensory input but in processing two at a time (Mundy, 1995). For example, if a child can attend only to his mother's facial expressions or hand movements and not concurrently to her voice, then this would constitute a handicap in trying to understand the mother's verbalizations. The Joint Attention Hypothesis bears a strong similarity to what other researchers have earlier referred to as 'stimulus over selectivity' or 'overly narrow attention' (Lovaas, 1979), which is reviewed below.

The term stimulus over selectivity refers to findings showing that children with autism initially respond to only one element, or a restricted range of elements, in a stimulus compound. For example, when presented with a teacher's verbal request, a child may either read the teacher's lips or attend to the teacher's gaze instead of responding to the teacher's voice. When learning to tell the difference between a girl doll and a boy doll, a child may make the distinction based on the dolls' shoes rather than more pertinent characteristics. When the teacher removes the dolls' shoes, the child may no longer be able to tell the difference between the dolls. In learning the meaning of a word such as mother, the child may have to associate two or more concurrent stimulus inputs, such as the spoken word 'mother' with the look, voice, feel, or other stimuli connected with her mother. Failure to associate these stimuli is likely to leave the word mother without meaning.

An alternate possibility is that restricted attention is not a causal variable per se, but rather the result of inadequate motivation and restricted learning opportunities. Over time, we have come to favour this possibility because over selective responding seems to diminish or, in the case of the best outcome children, vanish during intensive behavioural treatment without aides having to specifically address attention problems. It seems reasonable to assume that if an individual was not reinforced in past learning situations for attending to his social environment because he did not understand what was happening around him, then he probably would not have any reason to attend to his social environment in the present or the future. For example, imagine a student (who could be any one of us) attending a boring class in school and drifting off into various subtle forms of reverie and other forms of self-stimulation. After an hour of lecture, the individual would likely be unable to recall any part of the lesson, either in terms of what the teacher said or what was written on the blackboard. Conversely, if the same student attended a class in which a teacher broke down the lesson into manageable parts, spoke clearly, and provided ample reinforcement for participation, then it is likely that most or all persons in the class would attend to the lecture and learn. Similarly, if individuals with developmental delays are provided with learning opportunities in which they are systematically reinforced for attending to what others say or show to them, then the individuals may not show attentional problems when exposed to such events in the future.

Two observations led us to favor a learning hypothesis as it applies to treating attention problems. First, before treatment was started, the children we studied acted as if they could not see or hear unless they became confronted with a stimulus input that yielded a reward. For example, a particular child would not react to a loud siren and seemed completely oblivious to the people around her, only to spot a small piece of M&M candy some 30 feet away. Or, while appearing engrossed in a television show, a child would detect, out of the corner of his eye, that a parent went upstairs and left the front door unlocked. The child would then quickly go to the door, open it, and run away from the house, enjoying and being reinforced by the chase when discovered. Some children would always show up on time for their favourite television program and clearly identify the particular button that needed to be depressed to activate the system.

A pilot study done at the UCLA (University of California, Los Angeles) Autism Clinic provides a particularly vivid example of apparent sensory deficits in children with autism. In an attempt to ascertain where a nervous system sensory 'block' may be located, the children's heart rates, galvanic skin response, papillary dilations and constrictions, and orientation to stimuli were recorded. Clapping one's hands directly behind a child's back and observing a failure to startle is often used as a diagnostic indicator of autism. We failed to observe any response to hand clapping even though the clapping was loud. Subsequently, and without prior warning, we increased the loudness and fired a very loud noise (from a starting pistol) 2 feet behind each child's back. This sound was of sufficient strength to elicit a major startle in attending adults. In contrast, little or no change was detected in any of the children's behaviours, despite the sensitivity of the measurement instruments employed. However, there were major alterations in all recordings when, instead of firing the loud starting pistol, the children heard the slight sound of a candy bar being unwrapped out of sight. It seemed as if the children would attend to their environment if there was a payoff for doing so. In evaluating the outcome of this experiment, it is important to be reminded of the large differences among persons with autism. In regard to the experiment with the starting pistol, a child with a fear of unusual sounds, such as those from vacuum cleaners or ambulance sirens, may well have reacted differently from those children we observed in the study.

Other observations support the idea that learning is likely to be a major mechanism by which to establish attention. Discrimination learning provides such a mechanism by helping students attend to relevant stimuli such as the teacher's instructions. Teaching the student to discriminate among and attend to stimuli is reviewed in some detail in Chapter 16, and the steps involved are illustrated in considerable detail in almost all of programs presented in this manual. The teacher will discover that as students work through the programs in this manual, they gradually extend their attention to an increasingly larger range of stimuli if they are reinforced for doing so. Some of these stimuli are very subtle and require intact attention mechanisms.

Whereas some young typical children show evidence of stimulus over selectivity, some children with autism or developmental delays do not. Such an observation leads us to believe that restricted attention may be an effect, rather than the cause, of failure to learn. Nevertheless, restricted attention is likely to be present at the beginning of treatment, before the individual learns to attend to the teacher's stimuli. It is likely that the student will sometimes respond to cues the teacher inadvertently provides while ignoring those that the teacher intends for the student to respond to. For example, if the teacher were to accidentally look toward an object while asking the student to point to it, the student might solve the task by following the teacher's gaze rather than attending to the teacher's vocal instructions. Reinforcement for a correct response in such an instance would only serve to strengthen the wrong association between the visual cue and the student's response. It is very easy to make such a mistake. It is our observation that persons with developmental delays often learn an association when reinforcement is contingent on behaviour; however, this association may not be the one the teacher intended. We discuss ways of avoiding such problems throughout the manual.

Concluding Comments

Applied Behaviour Analysis has developed gradually and cumulatively, as discussed in Chapter 3. As findings emerge, older explanations are often revised or replaced by new explanations. A relatively recent observation sheds some new light on the attention problems discussed in this chapter. It appears that the mode by which students are taught makes a difference. That is, some students learn to respond to an auditory mode such as speech. Others experience difficulty learning when the teacher uses auditory cues, but excel when the teacher uses visual cues. Such variations in receptor preferences have led us to distinguish between visual learners and auditory learners This finding may help people view attention mechanisms from a new perspective. (See Chapters 12, 13, 29, and 30 for teaching procedures that accommodate visual learners.)



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