NEUROLOGICAL STUFF FROM TUKE'S PAPER

I now come to the last section of my paper:--

Cerebral Conditions Accompanying Imperative Ideas.

If now we consider what are the correlative changes in the cortex of the brain, we must say at once that no microscopical examination would disclose any pathological lesion associated with the morbid mental condition I have described. We are assisted, however, by starting with Laycock's doctrine of the reflex or automatic function of the cerebral cortex, as enunciated by him in a paper written fifty years ago. In this very original paper, read at York in 1844, before the British Association, he says of certain morbid mental conditions, that "their detection is sometimes difficult, because the patient being keenly conscious of his infirmities will conceal them. If, however, by what is termed the association of ideas, the morbid action of vesicular neurine be brought within the current of his thoughts, he becomes utterly powerless to resist it, as much so as the electro-biologised (hynotised) to resist the suggestions presented to their minds. The formation of these substrata is due to the fixity of the mind on one idea or class of ideas, at a time when, from morbid changes induced in the vesicular neurine (as by undue mental labour, intense emotional excitement, want of repose, the development of a dormant predisposition, and the like), it is unusually susceptible to the operation of the unconsciously constructing mind, so that the fixed ideas become deeply writ, as it were, on the vesicular neurine, in the same way as acquired instincts, habits, &c.; and are, in fact, as difficult to remove....

Laycock taught that "there is not only cerebral evolution in regard to healthy brain development, but an equally general inverse law of dis-volution (sic), equally important in studying mental disorders."

Laycock's theory fits in with the latent influence of association, not only of ideas, but of certain impressions received through the special senses, for in some forms of imperative ideas these become accidentally and sequentially connected in an extraordinary manner. The individual wishes to destroy this newly formed and accidental association, but he becomes absolutely dominated by it. Laycock, in his now little read article, insists that "the true explanation of the association of ideas is to be found in the doctrine of the reflex functions of the brain." (B. & F. Med. Review, January, 1845, p. 311), and yet, strange to say, no one except Dr. Jackson has done him justice, many have not once referred to him, and some have not heard of him!

Laycock recognised the control exercised by the cerebral cortex over sensory impressions, but does not appear to have anticipated current doctrines in regard to the control of one portion of the cortex over another, or positive and negative conditions of the mental functions. These doctrines it remained for Anstie, Monro, and above all Hughlings Jackson (who always expresses his indebtedness to them, and to Herbert Spencer), to teach.

I believe that Dr. Jackson has not in any of his writings referred specifically to imperative ideas other than as insane delusions [a position Tuke disputes], which according to him "signify evolution going on in the remains of a mutilated nervous system, as certainly as the patient's belief, when sane, signified evolution going on in the entire (i.e.) unmutilated nervous system." (Leeds Address by Dr. Jackson, 1889). There is in short a "dis-volution" of the highest cerebral centres...

Accepting this hypothesis, in addition to Laycock's great fundamental doctrine of the reflex or automatic function of the whole cortex, we seem to find an answer to the question I began with, what are the cerebral conditions accompanying imperative ideas? The most automatic is no longer under the control of the voluntary or least automatic cerebral levels or layers, or in Jacksonese, "reversals of evolution have occurred, being reductions from the least to the most organized of the highest cerebral centres."...

[Tuke now gives some illustrations.] With regard to the singular habit of touching certain objects without apparent reason, it is sometimes explained (by persons labouring under it) as due to a fear lest something will happen if they do not do it; but in other cases as an irrepressible habit without any motive whatever, often performed almost unconsciously as well as automatically. There may, however, be a conscious struggle between the voluntary or least automatic, and the most automatic cerebral action, the former being too feeble to control the latter. It often happens that ideas of touching are associated with ideas of doubt. In fact, "doubting Thomas" touches in order to satisfy his doubts.

Among the illustrations I have given of imperative ideas, the most curious, perhaps, is that of automatic counting. And yet the act of counting is one so peculiarly automatic that it is natural it should be performed by persons with weakened higher centres....

[Tuke goes on to raise questions about Hughlings Jackson's perspective on imperative ideas.] [W]e must, I suppose, assume that in the case of imperative conceptions without actual insanity, no pathological changes have induced dissolution of the very highest level or area....

From Daniel Hack Tuke, Imperative Ideas, Brain, 1894, 17:179-97.

 

Go to Rest of Tuke's Paper

 

Back to OCD History Home