The combination of perception of other individuals and exogenous manipulation of arousal enhances social facilitation as an aftereffect: re-examination of Zajonc's drive theory

Abstract

Zajonc's drive theory postulates that arousal enhanced through the perception of the presence of other individuals plays a crucial role in social facilitation (Zajonc, 1965). Here, we conducted two experiments to examine whether the elevation of arousal through a stepping exercise performed in front of others as an exogenous factor causes social facilitation of a cognitive task in a condition where the presence of others does not elevate the arousal level. In the main experiment, as an "aftereffect of social stimulus," we manipulated the presence or absence of others and arousal enhancement before participants conducted the primary cognitive task. The results showed that the strongest social facilitation was induced by the combination of the perception of others and arousal enhancement. In a supplementary experiment, we manipulated these factors by adding the presence of another person during the task. The results showed that the effect of the presence of the other during the primary task is enough on its own to produce facilitation of task performance regardless of the arousal enhancement as an aftereffect of social stimulus. Our study therefore extends the framework of Zajonc's drive theory in that the combination of the perception of others and enhanced arousal as an "aftereffect" was found to induce social facilitation especially when participants did not experience the presence of others while conducting the primary task.

Keywords: arousal; drive theory; observation; social facilitation; social perception.

FIGURE 1

Flowchart of the experimental procedure. The experimenter met a participant outside the experimental room and then they entered it together. The experimenter did not talk with the participant during this time. The participant was asked to conduct the task alone in accordance with a script that described the experimental procedure. And the experimenter demonstrated how to use the automatic sphygmomanometer and do the single-digit addition task. After providing participants with instruction, the experimenter left the experimental room. The participant conducted the addition task for the baseline. After the baseline session, the participants measured their arousal level using the automatic sphygmomanometer and by self-reports. Then, they spent 3 min in any one of the five conditions (see Methods), which were assigned at random by the experimenter. Before the test session, the participants measured their arousal levels. Then, they calculated the addition task as a test. Finally, participants measured their arousal levels again.

FIGURE 2

(A) Average number of values participants calculated during the addition task in the baseline phase and test phase. Error bars indicate the standard error of the mean in each condition. C, control condition; O, observed condition; G, greeting condition; E, exercise condition; OE, observed-with-exercise condition. *p < 0.05. (B) Mean values of SBP, HR, and self-reports at the baseline, after manipulation, and after test phase. Error bars indicate the standard error of the mean in each condition. (C) Averaged differences in single-digit addition task performance between the baseline results and the test session in each condition. Error bars indicate the standard error of the mean in each condition. C, control condition; O, observed condition; G, greeting condition; E, exercise condition; OE, observed-with-exercise condition. *p < 0.05.

FIGURE 3

Participants were divided into a high-score group and a low-score group on the basis of the median value in the addition task in baseline. The graph shows the average number of values participants calculated during the addition task in the baseline phase and test phase. Error bars indicate the standard error of the mean in each condition. C, control condition; O, observed condition; G, greeting condition; E, exercise condition; OE, observed-with-exercise condition.*p < 0.05.

FIGURE 4

(A) Average number of values participants calculated during the addition task in the baseline phase and test phase. Error bars indicate the standard error of the mean in each condition. C, control condition (main experiment); O + O, observed + observed at test condition (supplementary experiment); OE + O, observed-with-exercise + observed at test condition (supplementary experiment). *p < 0.05. (B) Mean values of SBP, HR and self-reports at the baseline, after manipulation, and after test phase. Error bars indicate the standard error of the mean in each condition. (C) Averaged differences in single-digit addition task performance between the baseline results and the test session in each condition. Error bars indicate the standard error of the mean in each condition. C, control condition (main experiment); O + O, observed + observed at test condition (supplementary experiment); OE + O, observed-with-exercise + observed at test condition (supplementary experiment).*p < 0.05; ** p < 0.01.