Attention mechanisms and inhibition of return in the somatosensory system.

摘要

The purpose of this dissertation is to add to the knowledge-base of attention in two ways. First, since only a few studies on attention have been performed in the somatosensory system, it will be demonstrated empirically how attention seems to operate in this system. Based upon these results, a model of attention will be proposed. One of the motivating factors for this research effort is that knowledge about attentional mechanisms dealing with the sense of touch may have implications for other behaviors, such as grooming behavior in both humans and animals. In addition, knowledge about tactile attention may be used to improve not only interpersonal interactions that require direct tactile attention (e.g. child rearing and romantic love), but also in the design of devices such as tactile aids for the deaf and blind, which may lead to improved health, quality of life, and the feeling of well-being. Such knowledge, furthermore, may be used to improve, or better understand, motor skills involving tactile feedback as well as lack of intentional actions of individuals with sensory neglect due to brain injury.;Second, this dissertation will address the issue of whether attention can be improved through learning. If training can lead to an improvement in a person's ability to attend, strategies could possibly be developed in order to improve sensory-motor performance. This would have implications for the treatment of clinical disorders as well as aid in the improvement of performance in the educational and entertainment arenas.;While the interaction of excitation and inhibition in responses due to attention for the visual system has been investigated (e.g. Posner and Cohen, 1984), the studies reported herein test a new specific hypothesis about the processes of attention that have never been directly addressed in any sensory system. That is, whether a detection time to a target, which is to be attended to, is a composite of at least two underlying mechanisms. These mechanisms, it is hypothesized, work in a push-pull fashion: one deploying attention when new events occur, and the other withdrawing attention (Posner's "Disengagement" process, see Posner 1980) after it has been deployed.