If there’s anything you can count on, it’s that change always occurs. What about the change that occurs in ourselves? Personal growth is achieved on nearly a minute-by-minute basis, and we’ve all looked back at previous chapters of our lives and realized that we aren’t quite the same person as before. Recent research uncovers how we form the basis of our identity and how our brains manage to keep the constant of our identity—even through the changes—intact.
The way we speak about ourselves and our experiences is defined by the moments when we use the word “I”. This pronoun creates the common thread that spans from our earliest memories across the length and breadth of our lives. Using the word “I” is a bridge between previous versions of ourselves and the person into whom we are evolving.
To study the details of how the brain organizes memories and anticipated future personal landmarks still yet to come, researchers at the University of Madrid designed a study to determine if we still recognize ourselves despite physically maturing. When we look back over photos of our childhood, what keeps us tied to that sense of self; and when we look so dramatically different than we once did, what clues our brains in that it’s still us and not a stranger?
This electrophysiological study focused on how the passage of time (known as temporal perspective) affects the core-self (the sense of identity and sameness). The researchers divided the study into two blocks: one to test recognition of self, friends, family, and unfamiliar faces; and life stage recognition. In each block, the twenty female college student participants were shown three pictures of a face (first, their face; then a close friend; then an unknown person). The photos of themselves were divided into different life stages (childhood, adolescence, and present).
The participants used a 3-button controller with corresponding buttons to indicate whether they recognized themselves, a close-friend, or an unknown person as the images were displayed. Similarly, they were asked to use the 3-button controller to discriminate between the three life stages during the other section of the experiment. Each participant was monitored with continuous EEG.
Identity was most noticeably activated within the central, anterior, and posterior brain regions. Differentiating identity between childhood, adolescence, and adulthood was most noticeable in the anterior brain region. Adolescence activated the brain more than images of childhood, which the researchers hypothesize is due the stability of identity during adolescence.
Results showed that participants distinguished past identity across time as separate from other identities. The researchers believe that knowledge of one’s self is not changed by the passage of time because it is affixed to episodic or semantic memory. This strings together a sense of self into a cohesive personal narrative, reinforced by the use of the word “I“.
Rubianes, Miguel, et al. “Am I the Same Person across My Life Span? An Event‐Related Brain Potentials Study of the Temporal Perspective in Self‐Identity.” Psychophysiology, vol. 58, no. 1, 2020, doi:10.1111/psyp.13692.