I chose to review this study because of its ecological validity. Ecological validity is a fancy term that refers to the applicability of empirical findings to real-world conditions. While there have been previous studies that have looked at the effects of peer presence or social cues on cognitive control, one could argue those studies have low ecological validity because in the real world, peer presence and social cues often occur together. This particular lab study has increased ecological validity because it examined the impact social cues, rewards, and the presence of peers had on the cognitive control of subjects ages 13-25 years old.
Subjects were divided into three groups: adolescents ages 13-17, young adults ages 18-21 and adults ages 22-25. Each subject participated in the “alone” or “peer” condition. While in an fMRI, subjects completed multiple trials of an adaption of a classic Go/No Go task. Participants saw one of three facial expressions or social cues (smiling, neutral or fearful) while waiting for one of three events to occur. The events were positive (receiving $100), negative (hearing a loud noise) or neutral (nothing occurred). During the trials, subjects pressed a button only when they saw a social cue that matched the initial social cue they were shown. So, if they initially saw a positive social cue (a person smiling) they were to press the button when they saw another smiling face and not press the button when they saw a neutral or fearful face. Not pressing the button was withholding the impulse. In the peer condition, while in the fMRI, subjects heard a “peer” of the same age and gender introduce themselves and say they were ready to begin. The peer in the peer condition was virtual, and the peer was not someone the subject actually knew.
The study generated two different types of results. One, was regarding behavior or accuracy – how well the subjects performed relative to three factors: peers vs. alone, type of social cues and type of anticipatory event. Adolescents performed better alone than in the peer condition, which was not the case for young adults or adults. When the social cue was neutral, adults performed better than adolescents. When anticipating a reward and receiving positive social cues, adults performed better than young adults or adolescents. Finally, when adolescents received positive social cues, they performed significantly worse in the peer condition than when alone which was not the case for the other two age groups. The second type of results were fMRI functional analysis – how the brain was functioning while the subject performed the task. Adolescents, unlike adults, showed more left orbitofrontal action in the peer condition than in the alone condition and greater orbitofrontal activity was associated with poorer performance. Taken as a whole, these findings demonstrate adolescents are more impulsive which results in negative outcomes in the presence of (virtual) peers, even when they get positive social cues and expect a reward.
In summarizing the findings, the authors noted, “As there were no developmental differences in performance in the alone condition for the combined positive arousal conditions (positive social cue and anticipation of reward), these data suggest that diminished cognitive control under contextually exciting and rewarding conditions may be exacerbated or amplified by the presence of a peer in teens.” The researchers go on to make an astute point—“Our findings suggest that previous empirical estimates of
contextual influences on adolescent decision-making may underrepresent the relevance of these influences when they co-occur, as is so frequently the case in naturalistic settings.” This study is important because it demonstrated how, as a normative developmental process, the presence of peers, and rewards, and social cues influences brain functions and resulting behavior. These data help further explain how adolescents, unlike adults, function differently and have worse impulse control and decision-making abilities when they receive positive social cues, expect a reward and are with their peers. The ecological validity of this study is great because in “real life” when a youth is in involved in an activity that brings them to the attention of the Court, often that youth was engaged in the alleged illegal activity with peers, who gave them positive social cues (a smile would be enough) and were expecting a reward. This study provides further evidence that under these “real life” conditions, a youth’s cognitive control system is not as engaged as it is for an adult in the same situation.
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 The repetitive use of the word and was done intentionally as a reminder that, unlike previous studies, this study was unique because it manipulated all three variables.