Is ADHD a hypo-attentional or hyper-attentional disorder?

Abstract

Explanations of attention date back to Aristotle, who considered attention as a "narrowing of the senses H, representing the selective aspect of perception. Attention Deficit Hyperactivity Disorder - (ADHD), is a neurobehavioural developmental disorder showing a marked impairment in the cognitive processes associated with the ability to maintain attention. An emerging alternative explanation for ADHD is that of 'Learned Inattention' - involving the inability to actively suppress the processing of irrelevant stimuli. This model assumes two concepts: Latent Inhibition (LI) (Lubow & Moore, 1959), referring to the delay in conditioning to a stimulus after preexposure and Kamin Blocking Effect (KB) (Kamin, 1969) that refers to the 'unlearning' of a stimulus added during conditioning to another cue. Research has already established a relationship between KB and LI with other neuropsychiatric disorders, such as OCD and schizophrenia. Moreover, this model also incorporates neurochemical (dopamine) abnormalities present in these disorders and hence provides neuropharmacological issues for consideration in the treatment of these disorders. We therefore wanted to explore the effect of KB & LI within a group of Maltese individuals diagnosed with ADHD, aged between 6-14 years. We used software based KB and LI tests comprising of a series of visual discriminatory conditioned association tests in addition to other structured questionnaires. Findings supported a novel 'hyper-attention' model of ADHD that may have implications to both the theoretical and practical management of ADHD, whilst also offering substantial diagnostic utility. Keywords: ADHD; Selective Attention; Associated Learning; Latent Inhibition; Kamin Blocking Effect.