Perceptual organization of acoustic stimuli by budgerigars (Melopsittacus undulatus): III. Contact calls

We trained budgerigars by operant conditioning to discriminate among a set of contact calls in a same-different task and analyzed response latencies from this task by using multidimensional-scaling (MDS) and cluster-analysis procedures. Humans listened to the same calls and indicated the similarity between pairs of calls by a direct rating procedure. An MDS program (sindscal) was used to arrange these complex acoustic stimuli in multidimensional space reflecting perceptual organization. Multiple regression techniques were used to identify the acoustic characteristics of contact calls that were correlated with the perceptual dimensions obtained from MDS. A number of spectral characteristics (e.g., peak frequency, rate of frequency modulation, and concentration of spectral energy) emerged as important for both budgerigars and humans, but the relative salience of these cues differed for the two species. Additional tests with two groups of budgerigars--cagemates and noncagemates--showed that experience with calls can change the salience of various acoustic characteristics used for perceptual organization and individual recognition.     

Confidence in judgments based on incomplete information: An investigation using both hypothetical and real gambles

This study assessed how confidence in judgments is affected by the need to make inferences about missing information. Subjects indicated their likelihood of taking each of a series of gambles based on both probability and payoff information or only one of these sources of information. They also rated their confidence in each likelihood judgment. Subjects in the Explicit Inference condition were asked to explicitly estimate the values of missing information before making their responses while subjects in the Implicit Inference condition were not. The manner in which probability information was framed was also manipulated. Experiment 1 employed hypothetical gambles and Experiment 2 employed gambles with real money. Expressed likelihood of taking gambles was higher when probability was phrased in terms of '% chance of winning' rather than '% chance of losing', but this difference was somewhat less with real gambles than with hypothetical gambles. Confidence ratings in each experiment were actually higher on incomplete information trials than on complete information trials in the Explicit Inference condition. Results were related to the general issue of confidence in judgments.     

Learning from lectures: The effect of varying the detail in lecture handouts on note-taking and recall

Previous research on the effect of lecture handouts on student learning indicates that students who are given skeletal handouts usually perform better in course examinations than students who take all their own notes. The present study investigates whether the amount of detail in the handout is a critical factor in this. A randomized groups experiment was conducted in the context of a course on dental surgery. Four lecture handout conditions (headings and full text; headings and key points; headings only; no supplementary materials) were compared on tests 2 days and 2 weeks after the lecture. The significant differences between conditions were: ‘headings only’ better than ‘headings and key points’ on the first test; ‘headings only’ better than ‘no supplementary materials’ on the second test; and ‘headings and full text’ better than ‘no supplementary materials’ on the second test. These results indicate that the amount of detail is a critical factor in handout effectiveness.     

Visual perception during naturalistic near-death out-of-body experiences

This study attempted to ascertain the most appropriate content and placement of visual stimuli in a hospital-based study of the veridicality of out-of-body perception in the near-death experience (NDE), and the likelihood that a subject in such a study would notice, clearly perceive, and accurately recall a visual stimulus. Based on the questionnaire responses of 63 subjects who had near-death out-of-body experiences (ND OBEs), at least some of the respondents described sufficiently complete and accurate visual perception during the experience to warrant the pursuit of veridicality research in hospitals. Recommended stimulus content for such research includes a surface with intense color and lighting, and simple number and/or letter combinations. Stimuli should be as far below ceiling level as possible while maintaining double-blind criteria. Some characteristics of the individual NDE and NDEr may affect veridical perception during the ND OBE.This paper was derived in part from her Ed.D. dissertation submitted to the Northern Illinois University Graduate School.     

Prophetic visions in 1988: A critical reappraisal

This paper reviews the research into a specific aspect of neardeath experiences (NDEs): the prophetic vision (PV). PVs are subjectively compelling flashforwards of planetary-wide cataclysms and eventual regeneration that sometimes occur during or in the immediate aftermath of an NDE. Previous research has shown that the most frequently mentioned year for the culmination of the geophysical calamities foreseen in PVs was 1988. I argue that PVs should be understood as manifestations of a collective prophetic impulse that historically tends to arise during periods of cultural crisis. PVs are thus expressions of the felt need for cultural renewal and therefore should not be taken literally as prognostic of drastic physical changes on Earth.     

Ego,moral, and faith development in near-death experiencers: Three case studies

Near-death experiencers (NDErs) commonly report shifts in basic values and attitudes, toward intensified compassion and a sense of unconditional love, sprituality, and a sense of mission, and away from materialism and competitiveness. Some researchers have suggested that these attitudinal shifts represent a new stage in human evolution, which will produce major social change. However, knowledge of these reputed NDE aftereffects has been based on NDErs' subjective reports, unverified by objective measures. This study examined relationships between three NDErs' levels of moral, ego, and faith development, as measured by standardized instruments, and extensive qualitative data describing their NDEs and personal attributes. The results suggest that currently available instruments, designed to measure the lower self, may not reflect the awakening to a transpersonal plane of functioning that follows an NDE.Dr. Newsome is in the private practice of psychotherapy and counseling. This paper was derived in part from her Ph.D. thesis submitted to Walden University.     

The Tichborne Claimant: Person identification following very long intervals

An account is given of the nineteenth-century case of the Tichborne Claimant, in which someone purporting to be Sir Roger Tichborne, a missing heir, arrived in England from Australia 13 years after Sir Roger had been assumed drowned at sea. Many people, including Lady Tichborne, Sir Roger's mother, positively identified him. Others insisted that he was an impostor. A civil court and a criminal trial each found against The Claimant for various reasons, but the question of The Claimant's true identity remains open to this day. The case of the Tichborne Claimant is used to illustrate issues in identification that are of contemporary interest. The particular matter of how faces change over time is briefly discussed.     

The masculinity—Irrationality relationship explored: Searching for a common denominator

The purpose of this paper is to explore the relative empirical support for two alternative ways of interpreting the relationship between masculinity and irrationality. The common denominator in this particular relationship was theoretically assumed to either reflect a person's locus of control expectations or his/her level of self-esteem.Two separate empirical studies were performed with groups of undergraduate university students. Both studies replicated earlier results, thus supporting the masculinity hypothesis as the one accounting for the relationship between sex-role orientation and irrationality.Of the two possible common denominators explaining this relationship, level of self-esteem was the one receiving the strongest empirical support. Some interesting gender differences concerning these two possible common denominators were also found.Ole Johan Hovland, Cand.paed., is Assistant professor of Personality Assessment at the Department of Personality Psychology, University of Bergen, Bergen, Norway, and maintains a small private practice in Laksevåg, Bergen, Norway. FranÇoise De Lange Alsaker, Cand.psychol., is a Research fellow in the field of personality development at the Department of Personality Psychology, University of Bergen, Bergen, Norway. Fred Vollmer, Mag.art., is Senior Lecturer in personality psychology at the University of Bergen, Bergen, Norway.