Experimenter bias and subliminal perception.

It has been suggested that subliminal perception phenomena may be in part due to experimenter bias effects. Two studies that obtained positive evidence of subliminal perception were therefore replicated with experimenters tested under blind and not blind conditions. There was only marginal support for the subliminal perception hypothesis and, although there were fairly clear indications of diffuse experimenter effects, the evidence for the experimenter bias explanation of subliminal perception was not strong. The need for more extensive replications of subliminal perception researches is noted. It is argued that the experimenter bias hypothesis lacks detail and generality; it is essential for it to be examined in the context of theoretically substantial issues.     

REFLECTIONS ON THE FIRST TWENTY YEARS OFCASIRAS: A PERSONAL REVIEW

Abstract. The history of CASIRAS and of Zygon is not only anintellectual history but a personal history-a history of humanencounter with hopes and disappointments, dreams and conces-sions. Notwithstanding, it is the story of an ambitious enterprisewith significant achievements and genuine promise of continuedcontributions to this important inquiry.     

A comparison of simple correction and functional feedback in schema learning

The role of knowledge of results (KR) in a schematic concept formation task was clarified by manipulating the specificity of information provided during feedback. Ss learned to discriminate between pairs of random forms from two schema families. Verbal correction was compared with a functional KR procedure in which the schema prototypes were superimposed over test stimuli. In no case did verbal correction improve learning in comparison with functional KR. Differences in acquisition persisted in a retention test.     

Tactile localization

Clinical studies suggested that errors of tactile localization made by leucotomized subjects were due to a failure of analysis of a conceptual type.

The present experiment examines the normal mechanisms of localizing stimuli to different sites on the hands by measuring the time taken to make a correct response as well as by an analysis of the errors made under conditions of stress (the reaction-time situation). It is demonstrated that healthy subjects of above-average intelligence have appreciable difficulty in determining which of their fingers has been touched. The degree of this difficulty depends on which finger has been stimulated. The results strongly support the hypothesis that normal tactile localization involves the analysis of primary sensory data in terms of a few simple parameters of orientation. It is suggested that some of the errors which occur are due to contamination between different systems of conceptual analysis.     

The effects of repeating a recognition test in lorazepam-induced amnesia: Evidence for impaired contextual memory as a cause of amnesia

In two experiments, a recognition test for an earlier presented list was given twice in immediate succession (Test 1 and Test 2). On the hypothesis that anterograde amnesia for episodic memory involves a deficit in contextual memory, amnesic subjects should confuse familiarity with distractor items gained during Test 1 with familiarity gained during original list presentation. As a result, they should think that they recognize more items on Test 2. This will lower recognition efficiency in Test 2 by increasing false alarms rather than by reducing hits. For subjects with an amnesia induced by lorazepam, but not for control subjects, recognition efficiency was substantially reduced in Test 2 in both experiments. As predicted, this impairment was due to a large increase in false alarms, with no decrease in the number of hits. The impairment could not be explained by a difference in recognition level between lorazepam and control subjects on Test 1. These findings therefore support the contextual memory deficit hypothesis of anterograde amnesia. Their implications for understanding the relationship between recall and recognition in amnesia are discussed.