Self-monitoring is a construct referring to individual differences in the way people monitor and manage their presentations of self, behaviors, and emotions. It was first proposed by psychologist Mark Snyder in 1974 in his article "Self-Monitoring of Expressive Behavior." According to Snyder’s formulation, people vary in the degree to which they attend and respond to social and situational cues regarding what behaviors are most appropriate. Essentially, variations in self-monitoring refer to variations in how willing or able people are to regulate their behavior and self-presentations in specific situations.
The Self-Monitoring (SM) Scale, developed by Snyder, captures differences in the kinds of cues to which individuals respond. It consists of items assessing how respondents observe, control, or regulate their expressive behavior in different settings. While there were twenty-five true-false items in the original scale, a revised eighteen-item scale is now more frequently used by researchers.
Individuals who score high on the SM Scale (high self-monitors) are concerned with the situational appropriateness of their behavior and are sensitive to social cues about what is correct behavior. They would agree with a scale item like "I would probably make a good actor." Regardless of how he or she really feels, a high self-monitor might be one of the most mournful of the mourners at a funeral held in the morning and then one of the happiest people at a party or wedding held later that same day. In contrast, those scoring low on the SM Scale (low self-monitors) are controlled more by their perceived internal feelings and attitudes and make little effort to fit the social situation. They would agree with a scale item like "I have trouble changing my behavior to suit different people and different situations." Low self-monitors might find it hard to hide their good mood even at a funeral. Alternatively, low self-monitors are more likely to show unhappiness at a party if they happen to be in a bad mood that day.
A great deal of research has examined behavioral differences between the two self-presentational orientations. For example, high self-monitors show greater cross-situational variability in their behavior than low self-monitors. Alternatively, low self-monitors are more likely to show high correspondence between inner attitudes and overt behaviors than are high self-monitors. These differences reflect the fact that high self-monitors are more likely to monitor their social environments, whereas low self-monitors are more likely to monitor themselves. Thus, it follows that among high self-monitors, aspects of the social self are more important, whereas the existential, experiential self (i.e., how one experiences oneself) is more important to the low self-monitor.
With regard to how these two self-types are related to psychological health, Snyder considers high self-monitors to be more pragmatic (or sensitive and strategic) across a number of social situations. Low self-monitors, on the other hand, tend to be more consistent with their principles and less responsive to situational or social pressures. Research suggests that personal problems are no more common among high or low self-monitors and that neither type is more susceptible to mental illness. Self-monitoring also seems to be unrelated to measures of neuroticism, anxiety, and depression.