40 AiTEREY Lewis 



When prooTcssivc dementia and focal symptoms, especially 

 apraxia, apliasia, agnosia, point to a cerebral degenerative 

 jmx'ess of the presenile Pick-x41zheimer type, and this is 

 conlirmed post-mortem, it is tempting to attribute all the 

 essential symptoms to cellular death in specified parts of the 

 brain; yet the cellular changes found in Alzheimer's Disease 

 have been found also in the brains of undemented old people. 

 The same can be said of senile dementia. The most obvious 

 explanation is that the cellular damage essentially respon- 

 sible for the dementing process is not disclosed by the histo- 

 logical methods of examination usually employed on the brain. 

 Alternatively, the brain — or the whole organism — may be 

 credited with such great powers of compensating for defect 

 due to local damage that mental abilities may seem intact in 

 one person while in another with a similarly damaged brain 

 dementia would be evident. Each of these views is open to 

 objection; they are not, of course, mutually exclusive and 

 may well be complementary. The neuropathologists will no 

 doubt sooner or later tackle the histological problem inherent 

 in the first: as for the second, psychologists have already 

 leant heavily on the concept of compensatory adj ustment in 

 explaining individual differences in degree and rate of 

 ageing. 



This concept — compensatory adjustment — is still imprecise, 

 but indispensable. The falling off in certain abilities; the 

 anxieties about one's material needs, health and survival; 

 the necessity for finding new social roles and preserving 

 social contacts, companionship and affection — these are 

 stresses which can only be met by adaptation calling for fuller 

 use of unimpaired abilities and opportunities to make up for 

 those that are lost. No doubt the ability to compensate needs 

 much analysis. It is hardly likely that the same ability is 

 responsible for the reorganisation of effector processes in a 

 skilled task and for the activation of an unsuspected potenti- 

 ality whereby social misfortunes or bodily decay can be coped 

 with. If the driving force is the need to maintain, in spite of 

 declining or defective ability, a standard of attainment, it is 



