ABSTRACT
This chapter is concerned largely with the forms or components of learned behaviour: the analysis of complex sequences into elements such as habituation, trial-and-error behaviour and so on not only makes description easier but also helps in the design of experiments. It begins with the systematic treatment of learned behaviour with an account of conditional reflexes (CRs). The systematic study of conditional reflexes reveals a number of regular, predictable but complex relationships involving the animal's internal state, external circumstances and previous training. Much of the great volume of researches on simple learned behaviour in mammals has been described under the heading of 'conditioning'; but usually both the methods used and the behaviour studied have differed in important ways from those of I. P. Pavlov. The most conspicuous feature of trial-and-error behaviour is of course the appetitive behaviour from which its name is taken. This is sometimes said to consist of 'random' movements.
