What Habituates in Infant Visual Habituation? A Psychophysiological Analysis

Abstract

Despite the use of visual habituation over the past half century, relatively little is known about its underlying processes. We analyzed heart rate (HR) taken simultaneous with looking during infant-controlled habituation sessions collected longitudinally at 4, 6, and 8 months of age with the goal of examining how HR and HR-defined phases of attention change across habituation. There were four major findings. First, the depth and topography of decelerations and proportion of sustained attention (SA) did not vary across habituation at any age, which suggested (in contrast to the tenets of comparator theory) the persistence of substantial cognitive activity at the end of visual habituation. Second, attention termination (AT) robustly declined across trials, suggesting that, contrary to prior thinking, AT might be a sensitive indicant of visual learning. Third, infants at all ages showed an HR increase (startle) to stimulus onset on the first trial, the magnitude of which was associated with subsequent delayed HR deceleration and less SA; thus, stimulus events affect processing Correspondence should be sent to John Colombo,

Zinc Supplementation Sustained Normative Neurodevelopment in a Randomized, Controlled Trial of Peruvian Infants Aged 6–18 Months

“…Mixed-model analyses of the proportion of time spent in orienting, SA, and AT did not yield any significant main effects or interactions involving supplementation. In keeping with other reports (45,57), the proportion of orienting increased with age (P = 0.009), and SA decreased with age (P = 0.008); no significant age effects emerged for AT. Figure 2 shows the typical HR response during various periods of a habituation trial and shows that the 2 supplementation conditions did not vary from one another in any meaningful way.…”

Temporal dynamics of arousal and attention in 12‐month‐old infants

“…This protocol measures infant's looks toward a static image, in a way that is identical to that used in previous research (Colombo et al, 2010). Results obtained were highly similar across the two analyses.…”

“…Traditionally, research based on look duration has measured the duration of looks to static (Colombo et al, 2010) or dynamic (Richards, 2004) images, generally presented on a computer screen. For the present paper, since we wished to analyse continuous looking data over a 20-minute period, we have recorded a slightly different measure -namely the duration of all looks towards the screen during the presentation of the entire mixed testing battery (described above).…”

“…Look duration is widely studied as an index of overt shifts of attention in infants, and considerable previous work has investigated the relationship between look duration and single indices of arousal, such as heart rate (e.g. Colombo et al, 2010;Richards & Casey, 1991;Richards & Gibson, 1997).…”

Prenatal Antipsychotic Exposure and Neuromotor Performance During Infancy

“…45 Future studies would likely benefit from a multimethod approach that incorporates infant behavior (eg, gaze) in combination with heart rate changes to better assess information processing capabilities. 46 …”