Mind Hacks has brought to my attention a number of interesting mirror-related studies:

Mirror Agnosia

[…] a condition where people lose their sense of reflection.

In these cases, the patient still has intact knowledge about mirrors, they can describe what they do and how they work, but they can’t seem to put it into practice.

For example, the patient stands in front of a mirror and the researcher holds a pen over the patient’s shoulder and asks him to reach for it. Most people would reach backwards, people with mirror agnosia reach forwards and bang their hand into the glass.

Mirrored-Self Misidentification

[…] a delusional variant where patients look into the mirror, see themselves, and believe it is another person.

How Big is Your Head?

[…] the mirror image of your head (as it appears to you) is exactly half its true size, irrespective of how far you are from the mirror, a fact that few people realise.

They also found that most people believe the mirror image of their own head will grow smaller as they move away from the mirror – it doesn’t it stays the same. Yet most participants correctly realised that if they watched the mirror image of another person’s head, it would get smaller as that other person moved away from the mirror. Finally, only a minority of participants realised that the size of the mirror image of another person’s head would get bigger as they, the participant, moved away from the mirror. Confused? Me too.

Me three.

This type of stuff absolutely fascinates me and is why I read—and highly recommend—Sacks’ The Man Who Mistook His Wife for a Hat.

Mirror Agnosia and Mirrored-Self Misidentification. How Big is Your Head?

The Psychology of Mirrors

Subjects tested in a room with a mirror have been found to work harder, to be more helpful and to be less inclined to cheat, [and] were comparatively less likely to judge others based on social stereotypes about, for example, sex, race or religion.

“When people are made to be self-aware, they are likelier to stop and think about what they are doing,” Dr. Bodenhausen said. “A by-product of that awareness may be a shift away from acting on autopilot toward more desirable ways of behaving.” Physical self-reflection, in other words, encourages philosophical self-reflection, a crash course in the Socratic notion that you cannot know or appreciate others until you know yourself.

via Mind Hacks

In 2006—to mark its three year anniversary—the British Psychological Society’s Research Digest asked some of the world’s best psychology bloggers to discuss a psychology journal article from the last three years which they found inspiring or that changed the way they think. The result: the best psychology articles from 2003–2006

• Just how good are police officers at detecting liars?
• Nice therapist, shame about the symptoms
• Psychology defined and unified
• Unusual experiences in everyday life
• Fusing psychology and neuroscience
• The route to happiness
• Expanding representations

All are fascinating articles.

Original archive video of Gibson and Walk’s Visual Cliff experiment: testing infant depth perception by getting them to walk over glass plates suspended above a drop.

The researchers wanted to find out whether 6 to 14 month-old infants could perceive depth.

The study put the infants, one at a time, in the middle of a table, with one side replaced by glass so you could see the ‘drop’.

Their mothers would try and tempt them over both sides, and if the kids had no depth perception, the glass ‘drop’ wouldn’t seem scary and they’d just walk straight over. Those who could see the ‘drop’ would avoid it.

Pretty much none of the infants wanted to walk across the ‘visual cliff’, suggesting that even kids of 6 months old could perceive depth.

But what of infants younger than this? When does depth perception develop?

In 1973, a study by psychologist Andrew Schwartz placed five and nine-month olds on each side of the ‘visual cliff’ and measured their heart rate.

When placed over the glass ‘drop’, the five month olds typically showed no increase in heart rate, suggesting there was no danger response. This suggests depth perception probably kicks in between about five and six months old.

via Mind Hacks