First impressions are based on a wide range of characteristics: age, race, culture, language, gender, physical appearance, accent, posture, voice, number of people present, economic status, and time allowed to process.
[11][12] People are fairly good at assessing personality traits of others in general, but there appears to be a difference in first impression judgments between older and younger adults.
Solo experiences tend to facilitate local processing, causing the viewer to take a more critical look at the target.
Simply priming viewers to feel like they were in solo or joint contexts or to process analytically or holistically was enough to produce the same viewing effects.
Some studies that manipulated media richness have found that information presented in text form yields similar impressions (measured by reported appraisal scores) among cultures,[19] while other studies found that richer forms of information such as videos reduce cross-cultural bias more effectively.
First impressions can be heavily influenced by a similarity-attraction hypothesis where others are immediately put into "similar" or "dissimilar" categories from the viewer and judged accordingly.
[24][25] When provided with descriptive information about a target, participants still rely on physical appearance cues when making judgments about others' personalities and capabilities.
Participants struggle to look past physical appearance cues even when they know information contrary to their initial judgment.
[25] Perceived competence level of a candidate measured from first impressions of facial features can directly predict voting results.
[26] In a 2014 study, a group at the University of York reported that people's impressions of the traits of approachability, youthfulness/attractiveness and dominance correlated with facial measurements such as mouth shape and eye size.
[29] Online profiles and communication channels such as email provide fewer cues than in-person interactions, which makes targets more difficult to understand.
In a study of online impressions, participants who were socially expressive and disclosed a lot about themselves both on their webpages and in person were better liked than those who were less open.
An additional study that looked at characterization of a romantic partner suggested that people are more likely to rely on "gut reactions" when meeting in person, but there isn't sufficient information for this kind of evaluation when viewing someone online.
[2][31][33] Straightening one's posture, leaning in slightly, and giving a firm handshake promotes favorable impression formation in the American business context.
[34] A qualitative review of previous literature looking at self-report data suggests that men and women use impression management tactics in the corporate world that are consistent with stereotypical gender roles when presenting themselves to others.
[9] Data collected from interviews with physicians distinguishes between first impressions and intuition and contributes to understanding the occurrence of gut feelings in the medical field.
[39] The posterior cingulate cortex (PCC), amygdala, and the thalamus sort relevant versus irrelevant information according to these biases.
[39] FMRI results show activation of the fusiform cortex, posterior cingulate gyrus, and amygdala when individuals are asked to identify previously seen faces that were encoded as either "friends" or "foes.
"[40] Additionally, the caudate and anterior cingulate cortex are more activated when looking at faces of "foes" versus "friends.
"[40] This research suggests that quick first impressions of hostility or support from unknown people can lead to long-term effects on memory that will later be associated with that person.
[10] One study tested stability by asking participants to form impressions people based purely on photographs.
[3] Assessment tools can influence impressions too, for example if a question provides only a dichotomous "yes" or "no" response or if a rater uses a scale (ratio).
Although this study was conducted with the intention of improving rating methods in medical education, the literature review was sufficiently broad enough to generalize.
[43] This phenomenon, termed the "halo-update effect," suggests that our initial assessments of someone's personality based on their attractiveness can be revised with updated information.