Stress reactivity speeds basic encoding processes in infants

Abstract

Acute stress attenuates frontal lobe functioning and increases distractibility while enhancing subcortical processes in both human and nonhuman animals (Arnsten, 1998, Arnsten et al., 1998, Skosnik, 1999. To date however these relations have not been examined for their potential effects in developing populations. Here, we examined the relationship between stress reactivity (infants' heart rate response to watching videos of another child crying) and infant performance on measures of looking duration and visual recognition memory. Our findings indicate that infants with increased stress reactivity showed shorter look durations and more novelty preference. Thus, stress appears to lead to a faster, more stimulus-ready attentional profile in infants. Additional work is required to assess potential negative consequences of stimulus-responsivity, such as decreased focus or distractibility.

How Infants' Arousal Influences Their Visual Search

“…This suggests that the increase in arousal may have enhanced the infants’ attention to novel stimuli. Previous studies have also suggested that infants who react with higher arousal to stress and sensory input may also be more attentive to faces, as well as to other salient stimuli (de Barbaro, Clackson, & Wass, ; Jones, Dawson, & Webb, ). This study sought to extend knowledge about this relation by experimentally manipulating short‐term arousal.…”

Physiological stress, sustained attention and cognitive engagement in 12-month-old infants from urban environments.

“…These changes are thought to be adaptive insofar as downregulated frontal activity and upregulated subcortical activity during periods of acute stress allows animals to more rapidly ascertain potential risks and respond to uncertainties in the environment with learned or pre-potent actions (Aston- Jones & Cohen, 2005;Dayan & Yu, 2003). Consistent with this, previous research examining a cohort of small-town dwelling infants has shown that infants with elevated physiological stress show both reduced visual sustained attention, and superior recognition memory for briefly presented images (de Barbaro, Clackson, & Wass, 2016b).…”

“…For example, previous research suggesting that increased physiological stress associates with both poorer sustained attention and superior recognition memory in a cohort of small-town-dwelling 12-month-old infants (de Barbaro et al, 2016b). Infant learning and attention is thought to be relatively more subcortically mediated than equivalent cognitive functions in adults (Colombo, 2001;de Barbaro et al, 2016b;Johnson, 1990), and previous research has suggested that recognition memory tasks may be subcortically mediated (Alvarez, Zola-Morgan, & Squire, 1995) -in contrast to sustained attention, which even in infants, is considered cortically mediated (Xie, Mallin, & Richards, 2018). The increased theta power we observed in HD infants was evenly distributed across the scalp (Fig 3), consistent with previous research (Jones et al, 2015;Orekhova et al, 2006).…”

“…Based on previous findings with infants (de Barbaro et al, 2016b;Wass et al, 2019) and similar results with adults (Arnsten, 2009) and based on previous results into the physiological effects of urban environments on older children (Evans et al, 2001), we predicted that infants raised in higher density (HD) urban environments would show elevated physiological stress, and that these changes would be accompanied by reduced sustained attention and increased emotion reactivity to a stressor. We also predicted that HD infants would show cognitive strengths: specifically, superior visual recognition memory and increased neural indices of cognitive engagement towards novel stimuli.…”

Understanding short-term interactions between arousal and attention in infants and children: applying the Aston-Jones framework

“…iii) Previous research has suggested that, whereas voluntary, 'top-down' attention control is highest during mid-level arousal, some aspects of memory encoding should be highest during hyper-arousal (Arnsten, 2009;de Barbaro et al, 2016;Wass, de Barbaro, et al, under review). Future research should explore in more detail the strengths, as well as the weaknesses, of the hyper-aroused behavioral phenotype.…”