Dilated Pupils: 10 Messages My Eyes are Sending You

Dilated pupils can reveal how hard we’re thinking, how excited or disgusted we are, whether we’re interested and more…

Dilated pupils can reveal how hard we’re thinking, how excited or disgusted we are, whether we’re interested and more…

Our pupils, the black holes which let light into the eyes, don’t just help us see, dilated pupils can also signal what’s going on in our minds.

Here are 10 pieces of psychological research which show how dilated pupils reveal many aspects of thought.

1. Dilated pupils mean I’m thinking hard

Look into my eyes and ask me to name the cigar-smoking founder of psychoanalysis and you won’t see much change in my pupil size.

The name Sigmund Freud comes easily to my lips.

But ask me to explain the laws of cricket and watch my dilated pupils.

That’s because research has shown that the harder your brain works, the more your pupils dilate.

When Hess and Polt (1964) gave participants more and more difficult tasks to complete, their pupils got bigger and bigger.

2. My brain is overloaded

Keep watching my eyes closely and you’ll spot the point when explaining the laws of cricket gets too much.

Poock (1973) reported that when participants’ minds were loaded to 125 percent of their capacity, their pupils constricted.

It’ll be trying to explain a googly that will do it. (Don’t ask).

3. Dilated pupils and brain damage

The reason doctors and paramedics flash a light in patients’ eyes is to check their brains are working normally (and because it’s such an easy test to do).

They use the acronym PERRL: the Pupils should be Equal, Round and Reactive to Light.

If my brain is broken, say, because I’ve had a bump on the noggin, you won’t see PERRL.

There may well be other extremely subtle clues, like the blood pouring from my head.

4. You’re holding my interest

Dilated pupils can also signal whether I’m interested in what you’re saying.

White and Maltzman (1977) had participants listening to excerpts from three books: one was erotic, another involved mutilation while a third was neutral.

Their pupils widened at first for all three. But they only remained wide for the passages that were erotic or involved mutilation.

I’m likely to be interested in anything new, so my pupils will dilate a bit at first, but they’ll only stay dilated if I continue to be interested.

5. You’re turning me on

If things take a sexual turn then our eyes are also involved.

Both men and women’s get dilated pupils when they are sexually aroused (e.g. Bernick et al., 1971).

However, not everyone agrees dilated pupils are a signal of sexual arousal.

It tends to get tested by showing nude pictures to people and some argue that we’re just really interested in the nude form.

6. Dilated pupils and disgust

Just as I have dilated pupils when I’m interested or turned on, so they constrict when I’m disgusted.

Hess (1972) showed people pictures of injured children.

First people’s pupils dilated because of the shock and then they constricted to try and avoid the troubling images.

7. Whether I’m liberal or conservative

Should you happen to be carrying around pictures of politicians you might be able to work out whether I’m a liberal or a conservative just from my pupil size.

Barlow (1969) showed people pictures of Lyndon Johnson, George Wallace and Martin Luther King, Jr..

The liberals’ pupils dilated when they saw fellow liberals Johnson and King but constricted when they saw conservative Wallace.

Conservatives showed the opposite pattern.

8. I’m in pain

If you’ve had enough of this article now and want to cause me some pain in return, then why not stab me with a pencil?

If you’re watching closely you’ll see my pupils dilate.

Chapman et al. (1999) fired small electric shocks into people’s fingertips and measured how much their pupils dilated.

At maximum intensity the pupils dilated by about 0.2mm.

But that was only to a relatively tame current.

Imagine what you could do to my pupils if you plugged me into the mains.

9. I’m on drugs

…and you can narrow down the type by looking at my pupils.

Some drugs, like alcohol and opioids cause the pupils to constrict.

Others, like amphetamine, cocaine, LSD and mescaline cause dilated pupils.

Police officers know this and some use it as one way of checking if someone is off their face.

They generally look for dilated pupils to either less than 3mm or dilated to more than 6.5mm (Richman et al. 2004).

10. My personality

This one is not strictly related to pupil dilation, but it’s too good to leave out.

If you look closely at the coloured part of my eye, the iris, you might even get some clues as to my personality (Larsson et al., 2007).

Look closely for ‘crypts’ in my eyes (lines going away from the iris, labelled 1 above) and this suggests I’m a warm, tender-minded person. If you see furrows (labelled 3 above), then, watch out, I’m impulsive.

It seems that the same gene, Pax6, which affects part of the brain associated with approach-related behaviours (the left anterior cingulate cortex, if you really want to know) also induces tissue deficiencies in the iris.

Dilated pupils

As you’ll have noticed, the same pupil response can mean different things, although generally dilated pupils send a positive message and when they constrict it’s a negative one.

But exactly what it means depends on the situation (and whether someone has turned on a light).

This is all good fun to know, but can we really detect these tiny changes in people’s pupil size?

According to an fMRI imaging study, change in pupil size may be difficult for us to notice consciously, but we do seem to pick up on these very small changes unconsciously (Demos et al., 2008).

So changes in pupil size may be experienced, along with other verbal and nonverbal signals, as a gut instinct to either approach someone or run like hell.

Whether or not the eyes are windows to the soul, the pupils are certainly windows to the mind.

Image credit: Larsson et al. (2007)

The Most Attractive Jobs For A Romantic Partner

Two dating apps suggest the most attractive jobs for both a man and woman.

Two dating apps suggest the most attractive jobs for both a man and woman.

Pilots, entrepreneurs, firefighters and doctors are the most attractive professions for men, dating app behaviour suggests.

For women, it is physical therapists, interior designers, entrepreneurs (again!) and PR people that top the list.

(If your profession isn’t here, check out the full list at the bottom of the article.)

At least these are the most ‘right-swiped’ professions on Tinder, according to the company.

Dating sites sometimes release these morsels of information and we have no idea how scientific they are.

Alternative claims for the most attractive jobs come from Badoo, another dating company.

Most attractive jobs for a woman

They surveyed 5,000 heterosexual men and women aged 18 to 30 in the UK.

Their list looks a little different — perhaps reflecting the cultural divide between the US and the UK.

For women, the most attractive jobs were:

  1. Hairdresser
  2. Nurse
  3. Lawyer
  4. Entrepreneur
  5. Teacher

Most attractive jobs for a man

For men, the most attractive jobs were:

  1. Chef
  2. Engineer
  3. Entrepreneur
  4. Marketing
  5. Artist

It seems, whether you are a man or a woman, using Tinder or Badoo, it is time to become an entrepreneur.

Oh, by the way, have I told you about the new company I’m starting up…

Most attractive professions on Tinder

And here is the full list of most attractive professions for women from Tinder:

  1. Physical Therapist
  2. Interior Designer
  3. Entrepreneur
  4. PR
  5. Teacher
  6. College Student
  7. Speech Language Pathologist
  8. Pharmacist
  9. Social Media Manager
  10. Model
  11. Dental Hygienist
  12. Nurse
  13. Flight Attendant
  14. Personal Trainer
  15. Real Estate Agent

The same list for men:

  1. Pilot
  2. Entrepreneur
  3. Firefighter
  4. Doctor
  5. TV/Radio Personality
  6. Teacher
  7. Engineer
  8. Model
  9. Paramedic
  10. College Student
  11. Lawyer
  12. Personal Trainer
  13. Financial Advisor
  14. Police Officer
  15. Military

The data was sourced from Tinder and Badoo.

Black Hair Is Attractive On A Woman, Research Finds

Long black hair was rated as more attractive than medium-length black hair in the study.

Long black hair was rated as more attractive than medium-length black hair in the study.

While black hair is attractive on a woman, lighter and longer hair makes women look more attractive in some circumstances, research finds.

Having lighter hair was most strongly linked to higher ratings for attractiveness, youth and health.

However, there were some kinks in the findings.

For example, having medium-length blonde hair was rated more attractive than long blonde hair.

Long black hair, though, was rated as more attractive than medium-length black hair.

The study’s authors describe their results:

“…we found that lighter hair (blond and brown) compared to darker hair (black) is generally associated with perceptions of youth, health and attractiveness, and generally leads to more positive perceptions of relationship and parenting potential.”

Black hair compared to brown and blond

For the study, 110 men looked at images of women with different coloured hair and of different lengths.

The hair colours were blond, brown and black and the lengths short, medium and long.

They were asked about the women’s relationship potential, age, health and parenting capability.

Longer hair, though, was linked to lower perceptions of parenting ability.

The study’s authors view their findings as supporting evolutionary theories:

“Hair that is healthy and strong signifies overall physical
health, which in turn can signify one’s capability of conceiving and carrying a child.

[…]

Because hair tends to be thicker, healthier, and grow more quickly in younger women (ages 16-24) than older women, one would expect that younger women would wear their hair longer than older women to provide a more perceptible and powerful signal to reproductive potential.”

Hair gets darker with age

Similarly, from an evolutionary perspective, blonde hair signals youth as people’s hair gets darker with age, until it starts to turn white.

Other studies suggest, though, that blonde hair only has a rejuvenating effect when women are under 40.

There is also evidence that preferences for blonde or darker hair depend on how prevalent that hair colour is in the area.

Men seem to prefer blonde hair more in areas where it is already more naturally prevalent.

The study was published in The Journal of Social Psychology (Matz & Hinsz, 2017).

Beards Are Attractive – If Facial Hair Is Correct Length

Beards and facial hair can be attractive — it depends what you want from a relationship.

Beards and facial hair can be attractive — it depends what you want from a relationship.

Women judge fully bearded men to be a better bet for long-term relationships, one study finds.

This might be because it makes men look more ‘formidable’.

Certainly, beards make men look older and more aggressive.

Beards are also often judged to make men look like they have higher social status.

However, for short-term relationships, women judge stubble to be most attractive, the research found.

Are beards really attractive?

However, whether or not beards are attractive to women is a big area of controversy in beard-related psychological research.

Some studies find that bearded men are more attractive to women than the clean-shaven, others not (e.g. Reed & Blunk, 1990Muscarella & Cunningham, 1996).

The most recent research goes against both beards and being clean-shaven and is starting to show the benefits of stubble.

But do women prefer light stubble or heavy stubble?

The jury is still out, with one study suggesting light stubble (Neave & Shields, 2008) and another heavy stubble (Dixson & Brooks, 2013).

Facial hair study details

The study showed pictures of men with different levels of facial hair to over 8,000 women.

Men’s faces were also ‘masculinised’ and ‘feminised’ by computer manipulation to see what effect this would have.

Here is an example of the feminised male faces along with different beard growths:

Here are the masculinised faces with different beard lengths:

The results showed that the more faces were masculinised or feminised, the less attractive they were.

Stubble is attractive

Stubble was most attractive to women in a short-term context and full beards most attractive when considering a long-term relationship.

The study’s authors explain:

“…beards may be more attractive to women when considering long-term than short-term relationships as they indicate a male’s ability to successfully compete socially with other males for resources.

Interestingly, a longitudinal analysis of men’s facial hair fashions in London from 1871 to 1972 revealed that beards became more common when the marriage market was more male-biased and the degree of intrasexual competition to attract mates was augmented.”

Beards and facial hair not universally attractive

Remember that all these are ‘average’ findings across thousands of people.

There are, obviously, both beard-lovers and beard-haters out there.

The study is the latest in a long and illustrious line of important beard-related research.

Not all studies agree on whether beards are more attractive, although stubble does seem to be emerging as a strong favourite, especially for shorter term relationships.

The study was published in the Journal of Evolutionary Biology (Dixson et al., 2016).

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