EXTERNALLY AND INTERNALLY CONTROLLED ATTENTION IN INFANTS - AN EEG STUDY

This work was designed to investigate EEG indices of Internally and Ex ternally Controlled Attention in infancy. EEG was recorded in 15 infan ts aged 7-8 months under three experimental conditions: (1) visual att ention to a new stimulation (Externally Controlled Attention or baseli ne condition); (2) attention guided by internal cognitive schemata dur ing 'anticipatory' phase of the peek-a-boo game (Internally Controlled Attention); and (3) 'reappearance' phase of the peek-a-boo game when the experimenter talked and smiled to an infant (reappearance). The re lative power (RP) in 4-5 single-Hz theta sub-band increased under both phases of the peek-a-boo game. The reactive changes of 4-5 single-Hz RP at prefrontal and frontal leads under the Internally Controlled Att ention condition positively correlated with the total time during whic h an infant was able to maintain ICA. The RP in 5-6 single-Hz theta su b-band significantly increased only under the Internally Controlled At tention condition and did not correlate with the total time of this ty pe of attention. The results support the concept of 'Diffuse Theta-Res ponse System' that is active during expectancy and effortfully focused attention. In contrast to theta, the RP in 6-7, 7-8, and 8-9 single-H z bands decreased during both phases of the game. The decrease was max imal at precentral leads and most probably reflected blockage of the s ensorimotor (mu) rhythm due to higher motility and muscular tension in the game situation. It is concluded that EEG is an adequate vehicle f or investigation of brain mechanisms of attention and voluntary contro l in infants. (C) 1998 Elsevier Science B.V. All rights reserved.