Savant-like Numerosity Skills Revealed in Normal People by Magnetic Pulses

  title={Savant-like Numerosity Skills Revealed in Normal People by Magnetic Pulses},
  author={Allan Snyder and Homayoun Bahramali and Tobias Hawker and D John Mitchell},
  pages={837 - 845}
Oliver Sacks observed autistic twins who instantly guessed the exact number of match-sticks that had just fallen on the floor, saying in unison “111”. To test the suggestion that normal individuals have the capacity for savant numerosity, we temporarily simulated the savant condition in normal people by inhibiting the left anterior temporal lobe of twelve participants with repetitive transcranial magnetic stimulation (rTMS). This site has been implicated in the savant condition. Ten… 

Figures from this paper

Autistic Number Learning What Autism

Autists count differently when compared with typically developing individuals. Autists differ from typically developing individuals in their counting skills by a slower reaction time when naming

Dynamic suppression of sensory detail saves energy

It is demonstrated that energy conservation is a possible cause of inhibition of sensory detail by high level concepts, and one of the reasons for this lies in the brain's need to conserve energy.

Explaining and inducing savant skills: privileged access to lower level, less-processed information

  • A. Snyder
  • Psychology
    Philosophical Transactions of the Royal Society B: Biological Sciences
  • 2009
It is argued that savants have privileged access to lower level, less-processed information, before it is packaged into holistic concepts and meaningful labels, which suggests why savant skills might arise spontaneously in otherwise normal people, and why such skills might be artificially induced by low-frequency repetitive transcranial magnetic stimulation.

Comment on Priming Skills of Autistic Twins and Yamaguchi (2006) Letter to the Editor: “Questionable Aspects of Oliver Sacks’ (1985) Report”, Journal of Autism and Developmental Disorders

Dear Editor, Oliver Sacks’ 1985 piece ‘‘The autistic twins’’ remains to this day the most compelling account of savant numerosity skills. Sacks broke the bewildering code of number communication that

Dissociable brain states linked to common and creative object use

The present experiment is the first to demonstrate a dynamic tradeoff between anterior frontal and posterior occipitotemporal regions brought about by the close‐ or open‐ended task demands.

Energy Saving Accounts for the Suppression of Sensory Detail

Computer simulations using a spiking neural network support the hypothesis that one of the reasons for high functioning autistic people’s exceptional skills with numbers, eidetic imagery and recall of concrete detail lies in the brain's need to conserve energy.

Transcranial electrical stimulation and numerical cognition.

  • A. SarkarR. Cohen Kadosh
  • Psychology
    Canadian journal of experimental psychology = Revue canadienne de psychologie experimentale
  • 2016
An assessment of the applications of transcranial electrical stimulation in the enhancement of aspects of numerical cognition, including numerosity, magnitude representation, and more complex arithmetic operations and the need to move toward greater ecological validity of experimental findings is assessed.



Savant-like skills exposed in normal people by suppressing the left fronto-temporal lobe.

Significant stylistic changes in drawing were facilitated by the magnetic pulses in four of the 11 participants, and some of these "facilitated" participants also displayed enhanced proofreading ability.

Switching Skills On by Turning Off Part of the Brain

Using repetitive transcranial magnetic stimulation (rTMS) to interrupt the function of the frontotemporal lobe, a region of the brain implicated in the development of savant skills, shows that savant-type skills improved in 5 out of 17 participants during the period of stimulation.

The 1988 Jansson memorial lecture. The performance of the 'idiot-savant': implicit and explicit.

  • N. O’connor
  • Psychology
    The British journal of disorders of communication
  • 1989
Although they cannot easily make clear how they carry out their tasks by using speech, experiments reveal that they follow simple rules which they use to aid them in recalling correct dates and sequences in classical music.

Hemispheric differences in the judgment of number

The Left Hemisphere's Role in Hypothesis Formation

It is concluded that the neural processes responsible for searching for patterns in events are housed in the left hemisphere, similar to how the right hemisphere of humans houses a cognitive mechanism that tries to make sense of past occurrences.

Left But Not Right Temporal Involvement in Opaque Idiom Comprehension: A Repetitive Transcranial Magnetic Stimulation Study

Left temporal rTMS reduced accuracy without differences between the two types of sentences, suggesting that opaque idiom and literal sentence comprehension depends on the left temporal cortex.

The development of arithmetical abilities.

  • B. Butterworth
  • Psychology
    Journal of child psychology and psychiatry, and allied disciplines
  • 2005
The evidence broadly supports the idea of an innate specific capacity for acquiring arithmetical skills, but the effects of the content of learning, and the timing of learning in the course of development, requires further investigation.

Task–specific impairments and enhancements induced by magnetic stimulation of human visual area V5

Data suggest that attention to different visual attributes involves mutual inhibition between different extrastriate visual areas, and TMS applied to V5 enhanced performance.

Arithmetic and the brain