STUDY OF NERVE CONDUCTION USING MODELS

Abstract

Nerve conduction, which is directly related with the trsns.is%tsn of asssagss in the living dy,hs become very interesting field in Biomedical for the lost few centuries. To study the phenomenon of nerve conduction, emphasis is made on the study of nsrvschsrsctartstiss, where the nerve membrsn. plays an important role. Chapter I deals with the introduction of nerve 'Conduction processes. All the post end the existing membrane roodgels are capable to explain only physiological behaviour associated with nerve m+ brane. Th. review of such type of nerve membrane modelling is given In the Chapter ii. Chspt.r III deals with the neurons* fibres, nerves and their r.spective rots in the nerve' canduttion. in this chapter the vsrittlons in electrical. characteristics of Nsrv. Ftbr.' with the changes in the physical dimensions are taken into account. In Chapter IV, the physical. behaviour of nerve membrane is discussed. Physical basis of Oxon action was suggested NLing.Y.W.i» In this theory of nerve conduction, the membrane is supposed to behave like a -Lv p "n 'p transistor with con emitter con figuration where the two Sides of the membrane set like two trsn-stator junctions. During the •vcttatiun stage, these junctions may ba replaced by the semi conductor diodes.. Ions in the nerve behave like electrons and holes in semt-conductor ; to the ionic currents may be expressed in terms of base and collector currents in a junction trans' later. Therefore, various physiological ,phenomena under rest and exciting conditions may also be satisfied both In quantity and quality. Membrane transistor oi's behaviour for ionic currents, action cotenttsl and time constants are similar to the membrane. Further, the behaviour of membrane trans - I, stor wod.t and *embrone are tdsVttcsl under hydrostatic pressure. The equivalent model of nerve membrane described In this dissertation deals wit ► the following points:- a) Ionic currents as junction currents* b) Threshold phenomena and 'AU-or-Nothing Law', c) Conduct ►nc, of sodium and potassium ions as a function of time and voltage, d Hydrostatic pressure effect on various currents with different stimulating voltages. Chapter V deals with the analysis of membrane tran s-aster model. The effect of prossurf on the membrane is also calculated. Conductivity modulation effect on membrane transistor model has also b.*n discussed . in this chapter. In Chapter VI experimental observations on trans-i stsr and d iod r membrane model are given. Further prospects In this area with the consider —a t ion of nerve esmbran a along with afferent and eff.rent signals are cited In Chapter VU