Abstract
The articles speak for themselves but a little editorial commentary may help to set the stage. First, what is meant by the term “dwellers.” It is clear from reading Barcroft's book that he is taking a broad view and including everybody who finds himself at high altitude. In other words he is not restricting dwellers to permanent residents. In fact the quotation comes from a chapter titled “Acclimatisation” and much of it deals with newcomers to high altitude including the lowlanders who were part of the expedition.
Earlier in the book in a chapter titled “The Colour of the Face and its Significance” which deals with cyanosis as evidence of reduced arterial oxygenation, Barcroft refers to three groups of people in Cerro de Pasco. These are the expedition members whose acclimatization consisted only of days or at the most weeks, the mining engineers who were previously lowlanders but had been at high altitude for months or years, and the native highlanders whose ancestors he argued had probably been at high altitude for many generations. Thus we have an interesting matrix of three groups of people who have been at high altitude for very different periods, and two types of physiological function, mental and physical powers.
Many of us would probably say that the answer as far as newcomers to high altitude is concerned is fairly clear. Every lowlander who goes to high altitude has a reduced maximal oxygen consumption for example. Also if he goes high enough there is clear evidence of impaired mental powers. Actually this was an area that particularly interested Barcroft and he made measurements of neuropsychological function that were some of the first that have been made at high altitude. He concluded that there was impairment of mental skills in that the expedition members were prone to make more errors than at sea level although when they were forced to concentrate on a particular task this could be accomplished. However he noticed that concentration was more difficult and time was wasted in trivialities and “bungling” as he put it.
When we come to the engineers who had been at high altitude for months or even years, the situation is not quite so clear. However most people believe that even after this prolonged time at high altitude, physical work capacity is reduced compared with sea level as is neuropsychometric function.
A far more difficult question is the physical and mental abilities of permanent residents or highlanders who have been at high altitude for generations. This case is argued by both Léon-Velarde and Basnyat and naturally there is a reluctance on the part of many people to regard highlanders as inferior in any way. Indeed Carlos Monge-Medrano who was responsible for the early study of Peruvian highlanders took great exception to Barcroft's statement (Monge 1948). In fact he argued that Barcroft could only have made these derogatory remarks about the Peruvian highlanders when Barcroft himself was suffering from Acute Mountain Sickness! Of course a major problem about drawing conclusions about highlanders is whom should they be compared with. Whereas the performance of newcomers to high altitude can be compared with their previous performance at sea level, this is clearly not possible for highlanders.
Whatever conclusions readers draw from the statements and rebuttals, I hope everyone will agree that Barcroft's provocative statement has raised some interesting issues and contributed further to our knowledge of high altitude medicine and biology.