The physiology of the tunnel

Several theories to account for the origin of tunnel hallucinations and tunnel experiences near death are considered: (1) the idea of a real tunnel; (2) representations of transition; (3) reliving birth memories; (4) imagination; and (5) physiological origins. Three different physiological theories are considered that related the tunnel form to the structure of the visual cortex. All can account for much of the phenomenology of the tunnel experience, and all lead to testable predictions. It is argued that the tunnel experience involves a change in the mental model of the self in the world. Because of this, an experience of purely physiological origin, with no implications for other worlds or for survival, can nevertheless produce lasting changes in the sense of self and reduce the fear of death.     

Building higher-order units in tachistoscopic identification: A test of two models

Summary Subjects were shown eight-letter pseudowords tachistoscopically and were asked to report as many letters as possible. The pseudowords, examples of either first- or fourth-order approximation to English, were printed in normal or reversed spelling and were presented in either normal of mirror-imaged letters. Finally subjects were either free to report in any order they wished, or they were instructed to report from left to right or from right to left. With normal letters, the familiarity effect was controlled by the spelling direction, not by the direction of report or the match between direction of report and spelling direction. With mirrored letters, however, order of approximation to English had no effect. The results contradict two existing theories: Mewhort's theory claims that the familiarity of fourth-order materials aids processing at a postcategorical level; it has trouble explaining why the familiarity effect disappeared with mirrored letters and normal spelling. Wolff's theory claims that familiarity aids processing at the feature level; it has trouble explaining why the familiarity effect disappeared with mirrored letters and reversed spelling.     

IS THERE A DISTINCTIVE QUANTUM THEOLOGY?

Quantum mechanics (QM) is a favorite area of physics to feature in “science and religion” discussions. We argue that this is at least partly because the arcane results of QM can be deployed to make big theological claims by the linguistic sleight of hand of “register switching”—sliding imperceptibly from technical into everyday language using the same vocabulary. We clarify the discussion by deploying the formal mapping of QM into classical statistical mechanics (CSM) via the mathematical device of “Wick rotation.” This equivalence between QM and CSM suggests caution in claiming distinctiveness for quantum theologizing. After outlining two areas in which quantum insights nevertheless resonate with longstanding themes in theological reflection (hiddenness and visualizability), we suggest that both QM and CSM point to a theology of science in which scientists participate in the divine gaze on creation as imago Dei.     

AUTONOMIC INDICES OF HABITUATION TO COMPLEX AND SIMPLE STIMULI

Skin conductance and heart rate were continuously recorded in 8 subjects repeatedly exposed to a perceptual-conflict test and to auditory signals. (1) Both complex and simple stimuli gave rise to a pronounced increase in skin conductance, the magnitude of response decreasing with number of repetitions. For both types of stimuli a linear relationship was obtained when GSR, measured as the change in log conductance, was plotted against the logarithm of the stimulus number. (2) Each presentation of the conflict test increased heart rate, magnitude of change decreasing approximately linearly with number of trials.