regarded simply as indices of emotion. One current line of research on the autonomic nervous system (ANS) and behaviour is that of ANS conditioning exemplified in the work of Black and his co-workers at McMaster (Black, 1959;Black, 1961;Black & Carlson, 1957) and in the experiments of Lacey andSmith (1954), and Notterman, Schoenfeld, andBersh (1952). I shall return to the subject of autonomic conditioning experiments presently.In our laboratory we have been concerned with the ANS in its correlations with skeletal motor activity, electroencephalograms (EEGs), incentive conditions, and performance. Initial experiments employed skeletal muscle potential recording only (Bartoshuk, 1955a(Bartoshuk, , 1955b but later experiments made use of various ANS measures in addition (Malmo & Davis, 1956). Results from these and other experiments with human subjects (Ss) which have been summarized elsewhere (Malmo, 1957) encouraged the idea that physiological recordings made at the periphery (i.e., from effectors) would tell us something about the nature of the central nervous system (CNS) mechanisms mediating the observed changes in performance. This work with human subjects preceded the animal work to be described later and, in a very real sense, led up to it. As I shall try to indicate in the following brief account, this rather long