Month: May 2013

Feeling someone else’s sensation of touch – the neural background, the examples, and you

Touch is the only sensation which we cannot share with another person. The immediacy of touch differentiates it from the distant impressions which sight and audition can give us. However, modern neuroscience is currently revising this picture: you can touch at a distance. One just doesn’t notice it. Can we find people who do?

A very possessive romantic partner may mind when his love interest was looked at. But it is a whole different game if touch was involved. There is something intuitively different about touch which pervades every day culture. It is, arguably, the lack of distance, the necessary intrusion of the touching object into personal space. This makes touching a very personal experience, far more so than seeing or hearing.
Modern neuroscience is currently revising this picture. The first report to challenge the immediacy of touch came out in 2004. A team led by Christian Keysers found that when people saw someone else being touched on the leg they showed activation in the same brain area as when their legs were being touched directly. Curiously, seeing touch from a first person perspective led to similar brain region activity as seeing it from a third person.
What it looks like to touch and being touched in the secondary somatosensory cortex.

What it looks like to see touch and being touched in the secondary somatosensory cortex.

This got several laboratories around the world started on the topic. For example, recently, Schaefer and colleagues showed that when hands are touched or seen to be touched, perspective does actually matter – a first person view-point increases activation more in primary areas than a third person perspective. In any event, the general picture was not a statistical fluke but instead a replicable finding – being touched is represented in a very similar way in the brain as seeing someone else being touched. But this raises two questions: why can’t I feel anything then and why does it happen?
In 2009, Ramachandran and Brang published a paper which may provide an answer to the first question. They studied four amputees who had lost one hand due to accident. When they watched an experimenter being touched on her hand, the lost hand’s phantom ‘felt the touch’ after a few seconds. One anecdote shows the power of this finding:
‘Patient 1 even added that after we had demonstrated this, he had gone home and asked his wife to massage her own hand while he watched, and watching her do so seemed to relieve his phantom pain.’
Importantly, this was not the case for intact hands – whether of control participants or the amputees. The difference, thus, appears to be whether the sensation felt by others is in competition with the own direct input from the skin. If so, the own touch wins the competition and one does not consciously feel someone else’s experience. But without a hand providing direct sensory input – as in the case of amputees – the touch felt by others becomes vivid.
Apes (of the non-human variety) collaborating.

Apes (of the non-human variety) collaborating.

This still leaves the question as to why this happens. The common explanation is that having the capacity to feel the touch of someone else – even if it is so faint as to be below the level of awareness – aids our ability to understand others. As a social species we need a high level of empathy in order to work together efficiently. Evolutionary ancestors who had a touch-empathy link may have been better at collaborating and, thus, were better able to survive and reproduce.
The current account makes an interesting prediction. Next time you have an anaesthetized hand or foot – and thus no own skin-sensation – you might want to check whether you can feel someone else’s touch. Let me know whether it worked. This experiment has not, as far as I can tell, be done, yet. You yourself could disprove the immediacy of touch.

Keysers C, Wicker B, Gazzola V, Anton JL, Fogassi L, & Gallese V (2004). A touching sight: SII/PV activation during the observation and experience of touch. Neuron, 42 (2), 335-46 PMID: 15091347

Ramachandran VS, & Brang D (2009). Sensations evoked in patients with amputation from watching an individual whose corresponding intact limb is being touched. Archives of neurology, 66 (10), 1281-4 PMID: 19822785

Schaefer M, Heinze HJ, & Rotte M (2012). Close to you: embodied simulation for peripersonal space in primary somatosensory cortex. PloS one, 7 (8) PMID: 22912698



1) adapted from Keysers et al., 2004, p. 337

2) By Ikiwaner (Own work)  via Wikimedia Commons

The ironic effect of German PhD prestige

What would happen if a culture actually believed that a PhD does confer such a great set of transferable skills and is such an important test of character that the title is a career boost? A look at Germany gives an impression but it is not the science policy heaven one might expect.


Schavan, Doktor, German science minister, doctor

By now she is just Schavan, ex-science minister.

There can be no doubt that a PhD is associated with career boost in Germany. Just look at numbers like these: in 2005 in the US 6% of CEOs had a PhD, in France it was 4%. In Germany, however, the number was a full 59%. Note that this is not because more than half of the university graduates who leave German universities do so with a PhD in hand. Only 11% do. Actual pay mirrors this pattern. With merely a university diploma a female graduate gets nearly a third less pay than her PhD colleague.The message to ambitious people is clear: get that PhD no matter what career you want to pursue.
Moreover, having a German PhD is more than just a boost to one’s career. It is a boost to one’s entire social standing. Once the title is obtained it will cover one’s doorbell, one’s business card and even one’s passport. One will expect to be addressed with this title. In many respects it has become the modern equivalent of a title of nobility.
At first, this may sound like science policy heaven. There is a country where people who have earned scientific qualifications have got such a high social standing that they easily reach the highest ladders of society. The claims of transferable skills, test of character, training in critical thinking and analysis, … There is seemingly no need to convince Germans of these things, no need to do advertisements for science education, it appears. However, the opposite could be true. People who want to reach the highest ladders of society are clogging up the scientific training process. They have their career in mind, not scientific progress.
Merkel, zu Guttenberg

He was defense secretary and had a PhD. She is chancellor and has a PhD.

This leads to unintended consequences. A year ago, the German defense secretary (Dr) zu Guttenberg was about to lose his PhD title for plagiarism and consequently stepped down. Now, the German science minister (Prof. Dr) Schavan was forced to resign for the same reason. In between, a list of other German politicians was also found out. When prestige is more important than scientific value, the latter will obviously suffer. In this context the list of people with faulty PhDs at the highest levels of politics is hardly surprising.
What needs to change is a view that people with a PhD are somehow better people. At heart, a PhD is just a vocational qualification for science, a necessary step for pursuing a career in research or academia. It says nothing about the general quality of a person, or as Chris Chambers put it: ‘almost everyone who starts a PhD and sticks around long enough ends up getting one’. Of course you learn transferable skills while doing a PhD, but this does not mean that a PhD should be seen as a condition for having a business or politics career.
Paradoxically, everyone involved might actually benefit from less prestigious academic titles in the long run. Professors would be less bothered by PhD students who are not interested in research. The research literature would be less clogged up with easily obtained but uninteresting findings. And career minded graduates would not be required to spend years of their lives developing research skills which will perhaps not be needed in their later business or politics careers.
Now, how do you reduce the prestige of academic titles? There is no better way than to expose people in power who obtained them without actually deserving them. Thanks Dr zu Guttenberg and Prof. Dr Schavan.



1) via

2) By Bundeswehr-Fotos [CC-BY-2.0 (, via Wikimedia Commons