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At present no student is free till his name is on theMedical Register, and the possibility of self-deter-mination is one of the most pleasant experiencesof those who qualify. Up to this consummationany degree of personal freedom within a medicalschool is hardly feasible except for those of excep-tional intellectual capacity. But there is no

necessity that the ideals of the schools should berestricted to the same extent. In fact the Londonschools give an exaggerated impression of uniform-ity ; in the provinces, where each universityconducts its own examinations, there is more

individuality which cannot develop in London,where not even the largest schools are allowed toescape the drab conformity of examinations overwhich they have no control. Elsewhere the coursesof teaching and learning are not all the same, noris the general colour of the schools altogethermonotonous. The predominance of physiology atOxford is almost an extravagant example ; nearlyall Oxford graduates may be expected to carry withthem at least traces of the unequalled course

directed by BURDON-SANDERSON, GoTCH, andSHERRINGTON. But a similar if less conspicuousdifference will be found between the men from

Liverpool, Leeds, and Glasgow; they have beenbrought up in schools where values are not exactlythe same and the product has a perceptible variety.

That there should be this variety we believe,with Sir CUTHBERT WALLACE, to be wholly to thegood. Sincere people doing their best to devisethe perfect curriculum will agree in all details onlyat the cost of unworthy compromise. Sincereteachers can standardise their teaching only bythe sacrifice of those personal ideals and charac-teristics by which alone teaching can inspire.Within reasonable limits, let each go his own way.Most medical students come away from theirschools with the impress of some particular teacherwho happened to attract them and to whose

teaching they attach exceptional importance. This

fortunately is beyond the control of any centralbody. The same liberty can surely be allowed tothe schools.

ANNOTATIONS

HEADACHE AND INTRACRANIAL PRESSURE

THE relationship of headache to intracranial pressurehas perplexed clinicians for many years, for it hasbecome evident that severe headaches may come onboth when the intracranial pressure is increased,as in intracranial tumour, and when it is diminished, asin lumbar puncture headache and some cases of

migraine. The discussion held by the section of

neurology of the Royal Society of Medicine on

Feb. 15th centred largely round this question. Severalpossible causes have been advanced to account forthe headache, such as uneven tension on the duralsepta (Trotter) or increases or decreases of tensionin the lateral ventricles (Elsberg). It is a commonobservation that the headache of intracranial tumourusually comes on after the patient wakes. Onlyoccasionally does it wake him up at night in spite ofthe fact that the intracranial pressure is greatest duringsleep. Since surgeons have made a practice of explor-ing the brain under local anaesthesia it has becomeevident that only certain intracranial structures aresensitive to pain. The brain tissue and most areas ofthe meninges are quite insensitive, but the dura materin the neighbourhood of the meningeal vessels, thelarger surface arteries of the brain (Penfield), and thevelum interpositum (Cushing) and choroid plexus ofthe lateral ventricles (Foerster) have been found to’be sensitive, and anatomists have shown these areasto be endowed with nerves. It has also become

increasingly evident that pain can only be perceivedthrough the medium of somatic afferent nerves. Thesympathetic system appears to have no afferent sideand to be incapable of transmitting pain. It is there-fore strongly probable that only those structureswhich are supplied with sensory twigs from the

trigeminal and vago-glosso-pharyngeal nerves can bethe site of origin of headache.The experiments with the headache of histamine

which were described by Dr. G. W. Pickering at thediscussion take us some distance towards an under-standing of the mechanism of headaches. Intravenousinjections of small doses of histamine acid phosphatefirst cause a fall of blood pressure associated with aTise of intracranial pressure ; as these are passing offheadache comes on and remains for several minutes

after both the systemic blood pressure and the intra-cranial pressure have returned to their previous levels.The headache is not directly due to the action ofhistamine, as with more prolonged instillations of thedrug the headache does not appear until its admini-stration is stopped. It can be relieved by inhalationof amyl nitrite, which dilates the cerebral capillaries,by compression of the jugular veins, or by any methodwhich temporarily reduces the pressure in the systemicarteries. But if the intracranial pressure is reducedby withdrawal of cerebro-spinal fluid, compressionof the jugular veins instead of relieving the headacheaggravates it. These observations suggest that thisform of headache is caused by some lack of balancebetween the pressures of the various fluid systemsinside the cranium represented by the arterial,capillary, and venous blood and the cerebro-spinalfluid. Dr. Pickering suggested that it was producedin some meningeal or vascular structure near thepoint of entrance of the internal carotid arteries. Itis evidently mediated by branches of the trigeminalnerve, since it never arose on the side of the head onwhich the Gasserian ganglion, or its sensory root, hadbeen destroyed. Dr. Pickering has also shown1 that theheadaches of everyday life can be modified in an

identical manner by alterations in the intracranial,capillary, or venous pressures. Lumbar punctureheadache behaved in the same way as histamineheadache after the withdrawal of cerebro-spinal fluid.He found however that the headache of meningitiscould never be abolished by such measures, althoughit might be reduced, and he suggested that there wasevidence here of direct irritation of sensitive areas ofthe meninges. Evidently the causation of headacheis not altogether a simple matter, but Dr. Pickering’sobservations have definite value in that they bothreduce the number of possible mechanisms and offersuggestions of treatment along rational lines.

LATE RESULTS OF MALARIOTHERAPY

WHILE few still question the immediate effectsof the malaria treatment of general paralysis, somehave expressed their doubts about its ultimateeffects. Prof. H. Claude and Dr. P. Masquin 2 have

1 Clinical Science, 1933, i., 77.2 Presse Méd., 1933, xli., 2005.