Abstract
When noxious unavoidable events (e.g., shocks) are signalled (e.g., by a 5‐sec. tone), it is widely believed that there is informational control (IC) in the sense that signalling reduces perceived event noxiousness; the IC mechanism arises through signal‐elicited preparatory anticipatory responses which reduce event noxiousness; there is a preference for signalled over unsignalled events (preference for signalling). Since these beliefs, though related, are different, the relevant evidence from the Toronto laboratory is presented separately for each bekf. That evidence, comprising studies published from 1970–1974 and some additional unpublished experiments, indicates: (a) no support for an IC mechanism in the electrodermal, plethysmographic, and cardiac response systems; (b) no support for IC itself with shocks and loud noises as noxious events; (c) no general preference‐ for‐signalling (PFS) phsnomenon (assertion based on total of over 570 Ss); but (d) a recent but consistently emerging specific PFS which appears based on Ss' (false) beliefs in the benefits of signalling. There follow some methodological claims which partially integrate the Toronto studies with apparently conflicting evidence from other laboratories. Complete integration involving a statement of the conditions under which signalling has beneficial, detrimental and no effects is not yet possible because of the empirical complexity of the problem, a complexity which requires an investigative rather than a demonstrational experimental approach. To illustrate the apparent strength of the latter approach, some examples are given of the current strong but unjustifiable Zeitgeist in favour of such beliefs as the generality of the PFS phenomenon in humans.