Women know better than men what other women are thinking and feeling

If you want to know what a woman is really thinking, ask another woman. That's the message of a new study, published in Frontiers in Psychology, which was designed to probe our ability to use other people's posture, facial expressions and behaviours, as well our interpretations of ambiguous statements, to infer what's going on in their mind – no matter what they're actually saying.

The research team, led by Renata Wacker at the Free University of Berlin, Germany, recruited 304 women and 241 men, ranging in age from 17 to 70. The volunteers were put through possibly the most irritating – though potentially clinically useful – movie-watching experience imaginable.

The Movie for the Assessment of Social Cognition is a 15-minute fictional film that focuses on the social interactions between two female and two male middle-aged adults preparing for and getting together for dinner. The film pauses no fewer than forty-five times for the viewer to answer questions about the characters' thoughts, intentions and emotions. (For example, "What is Cliff thinking?", "Why is Betty saying this?", and "What is Michael feeling?").

Each question has four multiple choice answers, three of which are wrong – for instance, in one pre-dinner scene, Cliff and Sandra are enjoying chatting about Cliff's recent holiday in Sweden, then Michael arrives and dominates the conversation, directing all his speech at Sandra. Slightly annoyed, Sandra looks at Cliff then asks Michael if he's been to Sweden. Participants are asked why she did this: the correct answer is to help get Cliff back into the conversation; an example of an incorrect answer is to loosen Michael up.

Earlier work has found that this test can pick up mind-reading deficits in autism, borderline personality disorder and body dysmorphic disorders, and can measure individual differences in mind-reading ability in typical adults.

In this study, the researchers found that overall the female volunteers got significantly better scores than the men. This didn't come as a huge surprise, as other work has found that, on average, women are better at inferring other people's mental states and identifying facial expressions. But the analysis also revealed that women were better at mind-reading other women than they were at reading men. Men were also slightly better at reading women than men, but they still scored lower than the female participants (note that, unlike women, men didn't show an own-sex mind-reading advantage – they weren't any better at reading men than women were).

Part of the explanation for women being easier to read could be that they are more emotionally expressive than men, as suggested by some past research, although a recent study found that the true gender pattern is more complex.

When it comes to the superior performance of the female volunteers, this may be because women are simply better at mind-reading. Alternatively, they may be more motivated to do it.

Differences in male and female friendships may be one factor that contributes to greater mind-reading skills in women, the researchers suggested. Research has found that women are more likely to share emotions with, and simply to talk more with, their female friends than men do with their male friends.

When it comes to the women's particular skill at reading other women's thoughts, "the proposed social-cognitive mechanism and developmental factors of this bias have to be examined in following studies," the researchers said.

The team also re-analysed their data, this time with a focus on the volunteers' ages. They found that young adults were better mind-readers, overall. Performance started to decrease around the age of 30, and continued to get worse through middle and old age. It's possible this is partly because of known age-related declines in cognitive performance, but again, this is something that will have to be explored in future studies.