Monday, 15 September 2014
The Intelligence in Our Hands
The first crisp days of autumn are great for outdoor chores like chopping firewood, installing storm windows, and raking leaves. Distracted by the blazing fall foliage, you may sometimes find yourself performing complex tasks with your hands while your mind is clearly off somewhere else. It’s as if your hands had “a mind of their own.”
But this mental aspect of manual work is not just a passing impression you may have; it’s also one of the hottest topics in cognitive science today. MIT Press has just published The Hand, an Organ of the Mind: What the Manual Tells the Mental. This collection of essays, edited by philosophy professor Zdravko Radman, examines the intimate connection between the hands and the mind not only from the neurophysiological and evolutionary angle, but from the philosophical, cultural and esthetic perspectives as well.
The “embodied” aspect of this hand/mind connection is, however, a theme that recurs throughout this collection. For example, one of the essays points out that the hands are the parts of the body that are most present to the brain’s visual system—so much so that the hypothesis that the brain creates a relatively stable visual space centred on the hands seems to be supported by various experiments. One example is the experiment in which a mirror box was used to give hand amputees the impression that they could see their missing hand being touched, thus reducing their phantom pain. Another example is the rubber-hand illusion, in which subjects who view stimulation of a rubber hand while receiving similar stimulation of their own hand perceive the rubber hand as part of their own body. Similarly, the book also discusses the phenomenon in which, when you use a tool repeatedly to interact with the space around you—a tennis racquet, for example—you come to perceive it as an extension of your own body.
In another essay in this book, Shaun Gallagher examines the hand from the standpoint of “enaction”—the particular type of embodied cognition proposed by Varela, Thompson and Rosch in the early 1990s. Gallagher defends the thesis that the brain, the eyes, and the hands form an overall system and that what we call rationality is actually something quite practical and action-oriented. He also examines the idea of “peripersonal space”—the space around us within hand’s reach, which helps us to create meaning through the exploratory and demonstrative capacities of the hand. Another contributor to this collection, Andy Clark, provides further evidence that our hands literally participate in our thought processes: he reports a series of experiments in which the subjects solved certain cognitive problems more successfully when they were allowed to make hand gestures as part of the process.
The book also looks at the many ways in which the hands can facilitate mutual understanding between individuals. One way is the gestures that accompany our oral language (which may itself have a gestural origin). The hands may also help us to generate and understand some of the more metaphorical aspects of spoken language, as well as to communicate entirely without spoken language, in the case of the sign language used by deaf people. (In this regard, if you read French, you may want to click the second link below, to find out about a course that UPop Montréal recently presented on issues in the Deaf community.)
The Hand, an Organ of the Mind also discusses some of the more controversial aspects of this enactive approach, which is increasingly popular in the cognitive sciences. For example, it compares the more and less radical versions of this thesis with the more traditional approach of symbolic representation and processing of information. Toward the more radical end of the spectrum, Etienne Roesch argues that the failure to integrate this enactive approach, which allows for constant adaptation to new environments, is slowing the development of several disciplines, and in particular robotics. Unless enactive concepts can be integrated into their design, the arms of humanoid robots, controlled by algorithms preprogrammed to deal with known environments, will continue to behave more like rigid assembly-line robots and less like naturally flexible human hands.
The Hand, an Organ of the Mind: What the Manual Tells the Mental
Le peuple de l’oeil : Enjeux de la communauté sourde
Body Movement and the Brain | Comments Closed
