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Biomedical subjects

G L Aiello

Publications and source records attributed to G L Aiello.

4 recordsLinked to original sources
PubMed1998

Multidimensional electrocutaneous stimulation.

Probing the subjective response to a five-parameter electrocutaneous stimulus has revealed a noisy perceptual space. A method for reducing the noise is hypothesized and experimentally tested by comparing the intensity discrimination thresholds along and off the energy gradient. Preliminary results show a reduction of the threshold of up to 60% when stimulating along the gradient. The method is exploited to implement an optimal intensity control in an electrotactile vision-substitution device.

Adult↗
PubMed1997

Brain cell microenvironment effects on neuron excitability and basal metabolism.

In a model of neurons in a brain cell assembly, changes in volume of the extracellular space affect neuronal excitability and basal metabolism. A widely applicable coefficient of excitability with respect to a variation of the volume fraction has been determined. Calculations suggest that chloride increases membrane stability by indirectly promoting an acceleration of the metabolic pumping rate as a response to a diminished extracellular volume fraction. Volume fraction changes induced by cell swelling in a compact and highly tortuous microenvironment may play a role in epilepsy and, following brain damage, in cell death and recovery.

Basal Metabolism↗
PubMed1996

Nerve length and volume in synaptic vs diffusion neurotransmission: a model.

Non-synaptic diffusion neurotransmission (NDN) may be an important factor in brain space and energy conservation, especially within cell assemblies and for mass sustained functions. We have illustrated the extreme cases of total synaptic and total ND neurotransmission for the purpose of noting the differences between the two. For these modeling studies, in which we assume assemblies of 1000 to 100 000 cells supplied by at least one fiber and a single synapse from each of the other cells, each cell assembly would have approximately 200 m to 8000 km of nerve fibers more than when innervated by diffusion. For coeruleo-cortical synaptic innervation, linking each to a common origin (the locus coeruelus), the fiber lengths are 38 cm (1000 cells) to 170 m (100,000 cells). It is likely , however, that neuronal arrays include both 'wireless' (NDN) as well as synaptic intercellular communication systems.

Brain↗