In a follow-up study published in a 1998 issue of Developmental Psychology, Povinelli and his research colleague Bridget Simon used nearly the identical procedure, but this time the study included five-year-olds and also included a seven-day comparison condition. That meant that, for half of the children, the time duration between the covert sticker-marking event and the video playback was a full week. In this study, 88 three- to five-year-old children were randomly assigned to either the brief delay (3 min) or the extended delay (7 days) condition. Similar to the results from the earlier study, less than half of the three-year-olds responded by reaching up to their heads regardless of the length of time that separated the two events. In contrast, nearly all of the four- and five-year-olds in the brief condition did so, and furthermore their same-age peers in the extreme delay condition did not. “That is,” the authors write regarding the delayed condition findings, “as age increased, the number of children who reached up tended to decrease…. Four- and especially five-year-olds displayed a clear understanding that although briefly delayed visual feedback is causally relevant to transient aspects of the present self, extremely delayed feedback is not.”
Povinelli has pointed out the relevancy of these findings to the phenomenon of “infantile amnesia,” which tidily sums up the curious case of most people being unable to recall events from their first three years of life. (I spent my first three years in New Jersey, but for all I know I could have spontaneously appeared as a four-year-old in my parent’s bedroom in Virginia, which is where I have my first memory.) Although the precise neurocognitive mechanisms underlying infantile amnesia are still not very well-understood, escaping such a state of the perpetual present would indeed seemingly require a sense of the temporally enduring, autobiographical self.
In this column presented by Scientific American Mind magazine, research psychologist Jesse Bering of Queen's University Belfast ponders some of the more obscure aspects of everyday human behavior. Ever wonder why yawning is contagious, why we point with our index fingers instead of our thumbs or whether being breastfed as an infant influences your sexual preferences as an adult? Get a closer look at the latest data as “Bering in Mind” tackles these and other quirky questions about human nature. Sign up for the RSS feed or friend Dr. Bering on Facebook and never miss an installment again.