Biomedical subjects

Stephen W Kercel

Publications and source records attributed to Stephen W Kercel.

4 recordsLinked to original sources

PubMed2005

Some radical implications of Bach-y-Rita's discoveries.

Bach-y-Rita's clinical results in restoring lost sensory function are based on several phenomena not widely appreciated in cognitive science. First, there is volume transmission. Extensive laboratory observation has shown that the brain is much more than a network of synaptically connected neurons. Bach-y-Rita has found that a key implication of volume transmission is that it is a functional component in adult brain plasticity, also widely observed experimentally. Plasticity has led him to conclude that the structure of brain dynamics is beyond the scope of algorithmic computation. If the brain is not a computer, this insight would have a significant impact on the development of new technologies based on brain function. Bach-y-Rita's work is being extended from restoration of lost senses to the creation of new senses. This in turn could lead to a new technology of "wiring a human-in-the-loop" that would be utterly unlike any computationally based technology. Instead of mere interaction with a machine, the human "becomes one" with it.

Brain↗

PubMed2004

The role of volume transmission in an endogenous brain.

Brain dynamics depends on synaptic, diffusive, and glial activities. Observations indicate that synaptic and diffusive activities modify each other's morphology, and glial activity modifies both. Synaptic activity modifies glial morphology. Whether diffusion modifies glial morphology has not been reported but it is reasonable to expect that it does. The relationship between these three transmission processes forms a closed-loop hierarchy of causation in brain dynamics, and the operation of that hierarchy may account for some of the seemingly bizarre properties of cognitive function.

Animals↗

PubMed2004

The endogenous brain.

Synaptic communication, nonsynaptic diffusion neurotransmission and glial activity each update the morphology of the other two. These interactions lead to an endogenous structure of causal entailment. It has internal ambiguities rendering it incomputable. The entailed effects are bizarre. These include abduction of novelty in response to conflicting cues, a resolution of the seeming conflict between freewill and determinism, and anticipatory behavior. Such inherent ambiguity of the causal entailment structure does not preclude the implementation of brain-like activities artificially. Although an algorithm is incapable of neuromimetically reproducing self-referential character of the brain, there is a currently-feasible strategy for wiring a "human in the loop" to use the cognitive powers of anticipation and unconscious integration to provide dramatic improvement in the operation of large engineered systems.

Algorithms↗

PubMed2003

Sensory substitution and the human-machine interface.

Recent advances in the instrumentation technology of sensory substitution have presented new opportunities to develop systems for compensation of sensory loss. In sensory substitution (e.g. of sight or vestibular function), information from an artificial receptor is coupled to the brain via a human-machine interface. The brain is able to use this information in place of that usually transmitted from an intact sense organ. Both auditory and tactile systems show promise for practical sensory substitution interface sites. This research provides experimental tools for examining brain plasticity and has implications for perceptual and cognition studies more generally.

Journal Article↗