Related to A. Chauveaux, 'On the Sensorimotor Nerve-Circuit of Muscles', Brain 14 (2-3) (1891), pp. 145-178.

Related to Henry Maudsley, The Physiology and Pathology of the Mind. 1867.
Description:

'The researches of Matteucci and Du Bois Reymond into the electrical relations of nerve have shown that there are currents of electricity engendered in nerve, as in other animal structures, which are constantly circulating in it When the nerve is active there is a diminution of its proper current, and the needle of a galvanometer connected with it then exhibits a negative variation. It has been supposed by Matteucci that there is a rapid succession of electric discharges from nerve and muscle during activity; but, although that assumption is very doubtful, and altogether ignored by Du Bois Reymond, there can be no doubt that the negative variation of the needle of the galvanometer marks a decrease in the electro-motive force of the nerve, and that this decrease is in some way intimately related to that molecular change in the interior of the nerve, which, when it reaches the muscle, will produce contraction, or when it reaches the brain, will be received as sensation." It is to be borne in mind that every minute particle of nerve acts according to the same law as the whole nerve ; the current, therefore, which a piece of nerve produces in a circuit of which it forms part, must be considered only as a derived portion of incomparably more intense currents circulating in the interior of the nerve around its ultimate particlea There is thus certain evidence, not only of the electro-motor properties of nerve, but of a modification of these during functional activity: such modification again testifying to an intimate change at any late in the polar molecules of the nerve.' (371-372)

 

From part I of 3rd (1876) ed.:

'Perhaps the most fit conception which we can form of the mechanism of the operation of ideation is that of a nervous circuit connecting a cell or a group of cells of each perceptive centre; a current of molecular action passing along this circuit would be the percept or idea of the object, and the current would naturally be excited at any point of the circuit to which the suitable stimulus could be applied. Obviously, however, the only points at which this could take place would be the cell-junctions, or the stations, so to speak, formed by the cell or group of cells of the respective perceptive centres included in the circuit. Herein then lies the physical interpretation of the psychological fact that the idea of an object may be aroused by any one of the sen- sations of which it is formed. Furthermore, when an idea is thus aroused through one sense, the perceptions of the other associated senses being understood or not realised, we may conceive that there is only a subactive state of their cell-junctions, which may be supposed to act as continuations of the nervous circuit, rather than in the perceptive or receptive capacity in which they may act when aroused into more intense activity by a stronger stimulus: we may regard them in the light of stations on the track through which quick trains pass without stopping, but at which other trains stop to take in passengers, and at which any train may be stopped if necessary. The supposition is in entire accordance with what we know concerning the regular process of conversion of nervous actions which were at first conscious into actions that are purely automatic.

When we rise from the percept to the concept, from the abstract of sensations to the abstract of perceptions, from representation to the representation of representations, by combining into one general idea that which is common to several ideas and rejecting that which is different in them, it will be necessary to imagine more complex groupings of nerve circuits. We may imagine a higher and more complex circuit in which the nerve circuits of the simple ideas now act as simple component units, taking the place in this circuit which the cell-junctions of the perceptive centres have in the nerve circuit ot the simple idea; the current of activity in the higher circuit will then be aroused by any one of these associated simple circuits, just as the current of activity in the simple circuit is aroused by any one of the associated perceptive centres, and may become, like it, after several repetitions of function, automatic. In it the representatives are, so to speak, re-represented. Multiplying these interconnected plexuses in accordance with the multiplication of our ideas, and associating them, as we must do, with corresponding motor plexuses in the anterior convolutions, we perceive the necessity of the infinitely complex mechanism of cells and fibres which form the cortical layers of the hemispheres. They constitute such a complex structure as the complex mental functions must needs have; for simple structures are capable only of simi)le functions. We may perceive also the reason of the necessity, if we would know the real value or mean-ing of the most abstract ideas, of seeking for it in the concrete ; we must pass from the higher nerve-circuit to the lower nerve-circuits of which it is representative, and from these again to the respective perceptive centres which they co-ordinate.' (280-282)

:

 

Related to J. Gaskell, 'The correlation of a sensation, an idea, and a thought', in J. Gaskell, New Elements from Old Subjects (1874), pp. 1-12.
Description:

Characterizes mind as dependent on two circuits, one of action and the other of reaction.

Related to L.S. Beale, 'Indications of the Paths Taken by the Nerve-Currents as they Traverse the Caudate Nerve-Cells of the Spinal Cord and Encephalon', Proceedings of the Royal Society of London 13 (1863-1864), pp. 386-392.
Description:

[NB: seee also Beale's Archives of Medicine iv (1859)]

Related to L.S. Beale, 'On the Structure and Formation of the So-Called Apolar, Unipolar, and Bipolar Nerve-Cells of the Frog', Philosophical Transactions of the Royal Society of London 153 (1863), pp. 543-571.
Description:

'The observations recorded... seem to show that a ganglion-cell may be developed upon a nerve-fibre already formed. Hence these ganglion-cells cannot be regarded as centres from which two nerve-fibres proceed direct to their peripheral distribution, but as centres placed at a part of a circuit which existed as a complete circuit before the ganglion-cell was developed in connexion with it.' (560)

Related to L.S. Beale, 'On the Ultimate Nerve-Fibres Distributed to Muscle and Some Other Tissues, with Observations upon the Structure and Probable Mode of Action of a Nervous Mechanism', Proceedings of the Royal Society of London 14 (1865), pp. 229-268.
Description:

The 'facts [in this paper] seem to render it probable that the fundamental arrangement of a nervous apparatus is a complete and uninterrupted circuit. This view is supported by the existence of at least two nerve-fibres in all peripheral organs and by facts observed in the branching and division of individual nerve-fibres and of compound nerve-trunks. I have also shown that in nerve-centres it is doubtful if apolar or unipolar cells ever exist. All nerve-cells have at least two fibres proceeding from them in opposite directions, and the multipolar cells in the brain and cord exhibit lines across them which are probable inidications of the paths taken by continuous currents which traverse them in many different directions.

The general inference from this anatomical inquiry is, that a current probably of electricity is constantly passing through all nerve-fibres, and that the adjacent tissues are influenced by the varying intenisity of this nerve-current rather than by its complete interruption and reestablishment; so far as I know, no fact has ever been discovered which would justify the conclusion that there exists any arrangement for making and breaking contact in any part of the nervous system. In all cases it is probable that every nervous circuit is complete, and that there is no interruption of the structural continuity of a nerve-fibre at any part of its course.' (268)

Related to W.B. Carpenter, Principles of Mental Physiology, 6 eds. (New York and London, 1874-1888).
Description:

'No Physiologist can doubt that the Mechanical force exerted by the Muscles is the expression of certain Chemical changes which take place between their own substance and the oxygenated Blood that circulates through them ; or that the Nerve-force which calls forth those changes, is intimately related to Electricity and other Physical forces. But this Nervous activity has its source in molecular changes in the Nerve-centres; the transmission of Nerve-force along the motor nerve being just as dependent upon Chemical changes taking place between the substance of the Ganglionic centre from which it proceeds and the oxygenated Blood that circulates through it, as is the transmission of an Electric current along the Telegraph-wire upon the Chemical changes taking place between the metals and the exciting liquid of the Galvanic battery. But these changes are themselves capable of being brought about by the various forms of Mental activity just enumerated. Just as a perfectly constructed Galvanic battery is inactive while the circuit is "interrupted," but becomes active the instant that the circuit is "closed," so does a Sensation, an Instinctive tendency, an Emotion, an Idea, or a Volition, which attains an intensity adequate to " close " the circuit, liberate the Nerve-force with which a certain part of the Brain, while in a state of wakeful activity, is always "charged." That Mental antecedents can thus call forth Physical consequents, is just as certain as that Physical antecedents can call forth Mental consequents; and thus the Correlation between Mind-force and Nerve-force is shown to be complete hoth ways, each being able to excite the other.' (14) [1876 ed.]

 

'It has been shown that the development of Nerve-force, whatever may be the mode in which it manifests itself, depends upon a reaction between the Nervous substance (especially its vesicular form) and the circulating Blood... And this Blood has a double function; for, on the one hand, it supplies the material at the expense of which the Nerve-substance is formed, or rather forms itself, by Nutritive action, and so, as it were, lays up a store of potential energy; whilst, on the other, it supplies the Oxygen, by the action of which upon the Nerve-substance (as in the oxidation of the zinc-element of the galvanic battery) this potential energy is converted into actual energy. Of this conversion we have the inost conspicuous example in the production of the Nerve-force which calls forth Muscular movement, and its transmission along the motor nerves; this production and transmission being extremely analogous to that generation of an Electric current, which takes place in a Galvanic apparatus of battery and wires, immediately that the circuit is closed. Now the ordinary state of activity of the Nervous system would seem to correspond closely with that of a moderately-charged Electric battery, which can be discharged by the completion of the circuit; this discharge relieving the tension for the moment, until it is restored by the chemical reaction between the blood and the ganglionic substance. And as there is strong reason to believe that the amount of the Nerve-force generated stands in no less direct a relation than the strength of the Electric current to the activity of that reaction, it is obvious that this, in its turn, will essentially depend on the amount of oxygenated blood which is allowed to pass through the capillaries of the ganglionic substance... an enlargement of the Arterial trunks, and an increase in the quantity of Blood which passes through the Capillaries — constituting the state termed hyperaemia — ecomes the cause of an augmented tension of the Nerve-centres; so that they are much more easily called into action by slight stimuli, and discharge themselves with greater force; whilst the tension may increase to such a degree, that a spontaneous Centric discharge takes place, analogous to that of an overcharged Leyden jar. — Under the guidance of this clue, it seems possible to arrive at a tolerably distinct conception of the nature of the Physical antecedence of every kind of Nervo-muscular action, from the simple Excito-motor up to the Volitional.' (380-381) [1876 ed.]