Tools for the body (schema)

Trends Cogn Sci. 2004 Feb;8(2):79-86. doi: 10.1016/j.tics.2003.12.008.


What happens in our brain when we use a tool to reach for a distant object? Recent neurophysiological, psychological and neuropsychological research suggests that this extended motor capability is followed by changes in specific neural networks that hold an updated map of body shape and posture (the putative "Body Schema" of classical neurology). These changes are compatible with the notion of the inclusion of tools in the "Body Schema", as if our own effector (e.g. the hand) were elongated to the tip of the tool. In this review we present empirical support for this intriguing idea from both single-neuron recordings in the monkey brain and behavioural performance of normal and brain-damaged humans. These relatively simple neural and behavioural aspects of tool-use shed light on more complex evolutionary and cognitive aspects of body representation and multisensory space coding for action.

Publication types

  • Review

MeSH terms

  • Animals
  • Behavior / physiology
  • Brain Mapping*
  • Cerebral Cortex / cytology
  • Cerebral Cortex / physiology*
  • Electrophysiology
  • Functional Laterality / physiology*
  • Hand / physiology
  • Humans
  • Learning / physiology*
  • Macaca
  • Man-Machine Systems
  • Motor Skills / physiology*
  • Movement / physiology*
  • Neurons / physiology
  • Task Performance and Analysis