Assessing visual STM in infants and adults: eye movements and pupil dynamics reflect memory maintenance

Though previous work has demonstrated substantial short-term memory (STM) development in the first year of life (e.g., Ross-Sheehy, S., Oakes, L. M., & Luck, S. J. 2003. The development of visual short-term memory capacity in Infants. Child Development, 74(6), 1807–1822. doi:10.1046/j.1467-8624.2003.00639.x), limitations in infant-based procedures make it difficult to assess the continuity of STM mechanisms from infancy though adulthood. The goal of the current work is to present data collected from both infants and adults using a novel STM assessment task. Eye-tracking was used to capture gaze and pupillometry in 5-, 8- and 11-month-old infants and adults (n?=?176). Infant data replicate and extend previous findings demonstrating clear evidence of STM improvement from 5- to 11-months-of-age. Analysis of adult data reveal qualitatively similar patterns of responding, and additionally reveal several behavioural markers of STM accuracy including pupil dilation, saccade count, and switching. These results suggest that change-detection tasks recruit similar memory mechanisms in both infants and adults, and further suggest that visual dynamics may provide important new continuous measures of STM from infancy through adulthood.     

Frequency of Nonsuicidal Self‐Injury in Adolescents: Differences in Suicide Attempts,Substance Use,and Disordered Eating

The relationship between frequency of nonsuicidal selfinjury (NSSI) and suicide attempts, substance use, and disordered eating was assessed in a community sample of 4,839 adolescents, 922 of whom reported NSSI in the past year. It was expected that the engagement in risk behaviors would significantly increase as NSSI frequency increased. Participants completed the Youth Risk Behavior Survey (Centers for Disease Control and Prevention, 2009) and were subdivided into five NSSI frequency groups: none, 1 time, 2–3 times, 4–5 times, and 6 or more times. A one‐way MANOVA found significant mean differences for all variables across NSSI frequency groups. The no NSSI group was significantly lower than all other groups on all variables. For suicide attempts, all frequency groups were significantly different from each other, with attempt frequency increasing with each increase in NSSI frequency. The six or more group reported significantly more substance use and disordered eating than all other groups. Overall, adolescents with more frequent NSSI represent a group at risk for concurrent unhealthy behaviors and suicide attempts.