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Studies combining electrophysiological and behavioral laterality measures hold great potential to illuminate hemispheric relations in attention. However, data from event-related potentials as well as spectral analyses (quantitative EEG and band power) are conflicting, and do not support a coherent theory of the electrophysiology of hemispheric attention. At the same time, a definitive behavioral measure of attention does not currently exist. To remedy these lacunae, we carried out the following experiment. Four groups of learning-disabled young adults received the same EEG biofeedback (EEGBF) protocol, consisting of training theta (4–8 Hz) down and training sensorimotor rhythm (12–15 Hz) up at four different electrode sites: C3 (seven subjects), C4 (ten subjects), Cz (nine subjects), and Fz (eight subjects). The C3 site is over the left sensory motor cortex, C4 is over the right sensory motor cortex, and Fz and Cz are over the front and middle regions of the central strip, respectively. Attention in each hemisphere was measured before and after EEGBF training using the computerized Lateralized Attention Network Test (LANT). The LANT estimates four separate networks of attention: executive-frontal Conflict resolution, the benefit and cost of spatial Orienting, and Alerting, or sustained attention. EEGBF affected different networks maximally at different sites: Training at C3 reduced Conflict in the right hemisphere, training at C4 improved Alerting bilaterally and training at Cz increased the benefit of spatial Orienting bilaterally. Generally, C3 training improved attention in the right hemisphere and C4 training improved attention in the left hemisphere. This suggests that training at C3 and C4 activates a metacognitive control system which is contralaterally organized. We concluded that EEGBF has site-specific and function-specific effects on attention. Further, unilateral training can have bilateral effects or even predominantly contralateral ones. This procedure suggests a new way to probe discrete physiological correlates of discrete behavioral changes following EEGBF. Such data inform functional theories of attention and clinical interventions in disorders of attention.

DOI: 10.1007/978-3-540-70573-4_7

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