Development of Preterm and Full-Term Infant Ability on AB, Recall Memory, Transparent Barrier Detour, and Means-End Tasks

Abstract

10 preterm and 10 full-term infants were tested longitudinally from 28 to 60 weeks of age on a modified version of the AB task, a nonreaching AB task, a Barrier Detour task, a Means-End task, and Perseveration in the Means-End task. Results show that age-corrected (age since conception) premature infants tolerated longer delays than full-term infants on the modified and nonreaching AB tasks. However, when compared by chronological age (age since birth), there were no group differences on either the reaching or nonreaching AB task. No group differences were found on Barrier Detour, Means-End, or Perseveration in either the age-corrected or chronological age comparisons. The results suggest that the function that mediates modified AB performance is one of memory and not of perseveration or means-end ability. Further, these findings suggest that current proposals about brain development based on single samples of infants may be tenuous. Finally, the results of this study suggest that development of the brain structure(s) that mediate modified AB performance is strongly influenced by experience in the postnatal environment.

Motor memory is a factor in infant perseverative errors

“…It is certainly plausible, therefore, that the same processes that lead to perseveration in reaching can lead to perseverative responses in gazing: repeated looks to one location lead to strong perceptual ± motor memories which capture succeeding looks. Indeed, there are several reports in the literature that such gaze perserveration may occur when infants are given A-not-B tasks where no reaching is allowed, although the evidence is equivocal (Hofstadter & Reznick, 1996;Matthews, Ellis & Nelson, 1996;Bell & Adams, 1999). This is a different issue, however, than whether just looking at a hiding event can lead to reach perseveration in the absence of reaching movements to that location.…”

Olfactory experience mediates response to pain in preterm newborns

“…For example, healthy preterm newborns have been found to learn to discriminate between odors (Goubet et al, 2002) or visual stimuli (Werner & Siqueland, 1978), to increase contact over time with an object providing tactile feedback (Thoman & Ingersoll, 1993), and to display an increase in heart rate when a gesture predictive of pain was administered . Although studies have shown that preterm newborns are less competent in processing information than full-term infants (Rose, 1983;Rose & Feldman, 2000), when healthy, premature infants were considered, no difference was found in later performance on the AB task (Matthews, Ellis, & Nelson, 1996). The works cited earlier seem to indicate an attunement to the environment and some of its characteristics, at least for healthy, preterm newborns.…”

Perception and production of object-related grasping in 6-month-olds

“…Parallel development was reported between manual and visual search responses in delayed response procedures challenging visuospatial memory (Pelphrey et al, 2004), in tolerated delays in reaching and nonreaching versions of A-not-B-error tasks in 7-to 15-month-olds (Matthews, Ellis, & Nelson, 1996), and in 8-month-olds' looking and reaching performance in an A-not-B-error task (Bell & Adams, 1999). In contrast, in a training study, Sommerville, Woodward, and Needham (2005) showed that prior experience with acting on a toy facilitated subsequent perception of an agent's goal-directed action on similar toys as seen before.…”