Acali,Ra 1, and Ra 2: Some conclusions and hypotheses concerning human friction under isolation and stress,with special reference to intelligence and personaiity assessment

Eleven adult volunteers - six females and five males - were left on a small raft in the Atlantic in order to study interpersonal relationships affected by family patterns of behavior, attitudes toward sex, race and racism, nationality, verbal and nonverbal communication, personality and character, intelligence, language, religion, leadership roles, and space. We hoped to gain a better understanding of friction and violence phenomena. The Acali experiment grew out of the more limited raft studies of Ra 1 and Ra 2. Intelligence and personality of the 11 members of the Acali raft expedition of 1973 were assessed by crew members and by shore-based scientists. Predictions concerning the Likely outcome of this long period of unavoidable proximity to 10 other individuals were made by a variety of scientists. Media treatment and views of friends and relatives were also studied. Some of the basic findings of the study were that assessments of both intelligence and personality carried out by these two methods were very different. Practising artists showed better predictive powers concerning the outcome of the voyage than either natural or social scientists. Media treatment influenced the views of the relatives of volunteers. It is suggested that laboratory assessments may not be related to assessed performances under stress, and that further progress in understanding human hostility will depend on a better knowledge of individual interactions.     

Subliminal action priming modulates the perceived intensity of sensory action consequences

The sense of control over the consequences of one’s actions depends on predictions about these consequences. According to an influential computational model, consistency between predicted and observed action consequences attenuates perceived stimulus intensity, which might provide a marker of agentic control. An important assumption of this model is that these predictions are generated within the motor system. However, previous studies of sensory attenuation have typically confounded motor-specific perceptual modulation with perceptual effects of stimulus predictability that are not specific to motor action. As a result, these studies cannot unambiguously attribute sensory attenuation to a motor locus. We present a psychophysical experiment on auditory attenuation that avoids this pitfall. Subliminal masked priming of motor actions with compatible prime–target pairs has previously been shown to modulate both reaction times and the explicit feeling of control over action consequences. Here, we demonstrate reduced perceived loudness of tones caused by compatibly primed actions. Importantly, this modulation results from a manipulation of motor processing and is not confounded by stimulus predictability. We discuss our results with respect to theoretical models of the mechanisms underlying sensory attenuation and subliminal motor priming.