Reflected glory

new_hair_mirror.jpgThere have been some critical commentaries recently that suggest that the hype over mirror neurons has become unbearable and a backlash is about to begin.

Mirror neurons are cells in the brain that are active both when a person is performing an action, or when they see someone else perform an action, and have been hypothesised to be involved in perceiving and comprehending others’ actions.

Worryingly, this system has been proposed as the basis of everything from empathy to appreciation of art, with very little supporting evidence.

Both Mixing Memory and Neurotopia have sceptical commentaries on mirror neurons and doubt whether they have been consistently demonstrated in humans in anything other than correlational brain scanning experiments.

This is probably a little unfair, as evidence for ‘mirror neurons’ in humans has been found using subdural (brain surface) electrodes, transcranial magnetic stimulation, fMRI, magnetoencephalography, EEG and when studying patients with action production and recognition problems after brain injury.

That’s quite a lot of converging evidence for the existence of an equivalent human system.

What is a little misleading is that the original studies measured the responses of single neurons in monkeys, whereby the human studies have all been using techniques that measured activation from a group of neurons.

This, and the fact that the recognition and generation of actions also relies on other brain areas, has led some to use the more accurate term ‘mirror system’ in preference to ‘mirror neuron’.

What most of the recent articles seem to be criticising, however, is that the concept is being used as a convenient ‘just so’ story for explaining almost any sort of complex human behaviour, usually by people with a fairly poor grasp of the existing evidence.

It’s easy to see why the idea is attractive. A system that is both involved in producing our own movements and becomes active when we see others moving leads some to infer (perhaps falsely) that we encode others’ behaviour into our brains in quite a direct way.

Even worse, in some retellings of the story, behaviour can include almost anything you care to think of.

As noted by Frontal Cortex, this concept, although flawed, is easy to grasp and user-friendly, making almost anyone an instant ‘expert’ on how the brain supports human interaction.

The reality will probably turn out to have too many qualifications to allow the media obsession with mirror neurons to continue forever, but in the mean time, don’t get put off by the hype.

The findings are fascinating and the mirror system will surely play an important role in our future understanding of human neuropsychology, even if this won’t exactly match how the media portrays it the moment.

Link to Mixing Memory article.
Link to Neurotopia article.

2 Comments

  1. Brandon King
    Posted July 27, 2006 at 8:28 pm | Permalink

    Thank you thank you thank you for the most well reasoned post I’ve seen on this topic lately.
    Does some type of mirror-behavior computational unit (single or group) exist? Yes. Does it mean that this is the cure all to every cogsci problem? No. What is means is that another piece of the puzzle is falling into place and there is alot of work to do as far as sorting out what processes this system cooperates with.
    Like any other significant finding, people take it out of context in some papers, but trashing the whole idea is downright wrong. How many papers do you see where some rare surface protein in some limited cortical area is discovered, and the discussion goes off on how this will end all mental disease? It happens constantly. Findings are made, people propose grand vision of their significance, other people try to assimilate the new info into their work, and the whole process snowballs. In the end, the fundemental beauty of the scientific method forces the inaccurate data and overstepping claims out. Why is the mirror-neuron system getting such a bad wrap lately? And why do some of these influential sites have posts on par with an undergrad’s mentality of neuroscience?

  2. Evil Monkey
    Posted August 5, 2006 at 2:57 am | Permalink

    Funny, I thought I was being supportive of the mirror system, just reminding people to be skeptical of what hasn’t yet been empirically demonstrated.
    Converging evidence for a mirror system, sure. I’ve got no problem with that. Show me a mirror neuron in a human though? You can’t. But many labs investigating these systems in humans explicitly attribute these cognitive functions to mirror neurons in journal titles and text.
    Nobody trashed the whole idea of mirror neural systems outright. I even admitted in my post that I’d be surprised if humans lacked mirror neurons themselves. Anybody who read otherwise in our posts doesn’t even have an undergrad’s concept of skepticism.
    PS- Nice summary, Vaughn.


Post a Comment

Required fields are marked *
*
*

Follow

Get every new post delivered to your Inbox.

Join 22,429 other followers