[Experimental bases for evaluating attention in attention deficit hyperactivity disorder].
BACKGROUND
The experimental evaluation of the time variable in attention enables us to distinguish between what can be considered as its normal and its pathological behaviour. It has proved to be useful in evaluating the population suffering from attention disorders (attention deficit hyperactivity disorder, frontal lesions, etc.) as a means of defining the extent to which the patient is affected by the disorder and also in designing a training programme for later use.


METHODS
The most notable attentional paradigms are attentional blink (AB), repetition blindness, change detection, psychological refractory period, task switching, and negative and positive priming. Patients with ADHD showed a poor capacity for identification of target stimuli (T1) in attentional blink tests; they also displayed a significantly higher attentional blink than that observed in the control group, especially for time intervals between 300 and 600 ms after the first target letter (T1).


CONCLUSIONS
Attention is a complex, dynamic concept derived from the interaction of different neuroanatomical systems. There are several different theories to explain disorders affecting the attentional skills. One of the explanations comes into being as a result of linking sustained attentional disorder with impulsiveness and hyperactive behaviour. Another is related to selective attention disorders. This distinction allows us to discern the involvement of two systems that will give rise to different clinical symptoms and hence the presence of attentional subtypes. Thus, for example, it is possible to find a first group with disorders affecting attention, impulsiveness and disinhibition, and a second group with slow reactions and in a state of confusion and/or inattention as regards the events taking place around them (but they do not have impulsiveness or disinhibition).
Etchepareborda
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Centro de Neurodesarrollo Interdisciplinar, Valencia, España. red-cenit@telefonica.net
D001288:Attention / Q000502:physiology*; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D001767:Blinking; D006801:Humans; D007175:Impulsive Behavior; D009483:Neuropsychological Tests; D011930:Reaction Time