It is rare to meet with troubles of micturition, nocturnal enuresis scarcely deserving mention owing to its frequency among all young degenerates and to its being so commonly the outcome of neglect. Oppenheim,[58] however, considers diurnal enuresis worth including in the symptomatology, and Brissaud[59] has described polyuria and pollakiuria in association with obsessional preoccupation. These are really functional disturbances in which increased desire is followed by increased vesical action, and may be regarded, if one likes, as micturition or sphincter tics.[60]] AFFECTIONS OF SENSATION Generally speaking, objective disturbances of sensibility do not occur, and while subjective changes are more frequent, they may be entirely lacking even in long-standing and aggravated cases. What the patients usually complain of is a more or less persistent, disagreeable, uncomfortable sensation, rarely described as painful, and often compared with a feeling of stiffness or fatigue. Or, again, they may be conscious of a sense of constriction or of dragging in the affected muscles, either at their insertions or in the muscle belly, or sometimes in the joints concerned. These subjective sensations are characterised by extreme variability in time and in degree. Moreover, the accounts given by patients of their own sufferings ought to be accepted with reserve. Not merely are they ready to exaggerate and incapable of accurately depicting and localising their sensations, but they also exhibit a curious tendency to false interpretation: they attribute an erroneous pathological significance to their feelings, and proceed to elaborate a thousand ridiculous variations, thereby inviting in a sense the eruption of fresh tics. In all this behaviour their mental imperfections are abundantly manifest. We may remind ourselves in this connection how O.'s various inventions had no other effect than that of provoking new tics, and another illustration is to hand in the case of S., an account of whose mental torticollis will be found in a previous chapter.