Later, during the formal study, test subjects were asked to evaluate a hypothetical person who had "neutral" characteristics such as cautious, determined and industrious.
Statistically, women and men judged the hypothetical person in similar ways. But those who were asked to hold the iced coffee gave more negative or "cold" attributes like selfishness to the person, while those who held the warm cup of coffee rated the same person with "warm" attributes like generosity.
The study may gives a clue on whether to get coffee or cold drinks for a first date, but it also adds yet another connection between our physical comfort and how people judge social interactions.
Judgments Based on Mood, Not Good Judgment
"In psychology we tend to underestimate the influence of the physical environments on our thoughts," said Lawrence Williams, a co-author on the study.
In a second study, Williams and professor John Bargh of Yale University, his co-author, gave 53 test subjects hot or cold packs to evaluate under the guise of a product study.
Afterward, the group touching the cold packs were more likely to act "cold-hearted" by choosing a small giveaway prize for themselves, while the group touching the hot pack was more likely to choose a giveaway gift certificate for a friend.
"These fundamental physical influences on people matter. ... Our bodily experiences matter in terms of our state of mind," said Williams, who is now an assistant professor of marketing at the University of Colorado at Boulder.
Cold Hands, Cold Heart and Beyond
Kareem Johnson, a professor of psychology at Temple University in Philadelphia, agrees.
"This study is new in the measurement or the technique, but it's entirely consistent with previous research," said Johnson, who was not involved with the study.
Johnson studies how emotions may influence a person's perceptions of people of a different race. Although Williams hypothesized that the warm-hand connection to warm-personality traits stems from safety associated with the warmth of being held as an infant, Johnson has seen other physical-judgment connections.
"There are all sorts of things that can influence our judgment that have nothing to do with actual judgment," Johnson said.
For example, Johnson has found that whether a person is asked to push off from a desk with their hands on top, or pull in with their hands below, will influence whether they make positive or negative judgments.
"It's actually quite difficult to evaluate others," Johnson said. "You could go through a very logical, systematic way of doing things. But oftentimes what we do to make our judgment simpler, is we go with how we feel at the moment, even if it's subconscious."
Both Williams and Johnson said this physical influence on mood and, subsequently, judgment only goes so far.
"If it's a brand new judgment and one that's open to a lot of ambiguity, then these things can matter," Johnson said. But for more important decisions, or decisions where we are armed with information like when we're choosing a doctor, Johnson said your physical state and mood matter less.
Mind-Body Connection Is Strong
In more serious social situations, other research has confirmed a judgment-body temperature connection, but in reverse. It turns out harsh judgments can literally feel like a cold shoulder.
Researchers at the University of Toronto published a study last month that showed when people are socially excluded they report a colder guess of the room temperature, while people who have been socially accepted report a much higher room temperature.
According to the study, published in the journal Psychological Science, individuals' estimates ranged from 54 degrees to 104 degrees in the same room.
Subconscious Judgments Are Common
"Many of these things happen unconsciously," said Chen-Bo Zhong, a co-author of the September study and an assistant professor in the department of organizational behavior and human resource management at the University of Toronto.
"Even though sometimes you may experience cold or warm, you may not be able to know what really caused it," he said.
"That's the beauty of the Lawrence study, is that all these effects on judgment were unconscious," Zhong said, who was not involved with the study. "If you ask people to recall, they wouldn't be able to tell you explicitly why."
In the future, Williams would like to look at other sensory influences such as soft or hard objects.
"What are some other types of fundamental aspects of the physical world that can play a meaningful role in the psychological judgments people make?" said Williams.