Equal Familiarity Research Articles

Erratum to: The effect of self-explanation of pathophysiological mechanisms of diseases on medical students' diagnostic performance.

Self-explanation while diagnosing clinical cases fosters medical students’ diagnostic performance. In previous studies on self-explanation, students were free to self-explain any aspect of the case, and mostly clinical knowledge was used. Elaboration on knowledge of pathophysiological mechanisms of diseases has been largely unexplored in studies of strategies for teaching clinical reasoning. The purpose of this two-phase experiment was to investigate the effect of self-explanation of pathophysiology during practice with clinical cases on students’ diagnostic performance. In the training phase, 39 4th-year medical students were randomly assigned to solve 6 criterion cases (3 of jaundice; 3 of chest pain), either self-explaining the pathophysiological mechanisms of the findings (n = 20) or without self-explaining (n = 19). One-week later, in the assessment phase, all students solved 6 new cases of the same syndromes. A repeated-measures analysis of variance on the mean diagnostic accuracy scores showed no significant main effects of study phase (p = 0.34) and experimental condition (p = 0.10) and no interaction effect (p = 0.42). A post hoc analysis found a significant interaction (p = 0.022) between study phase and syndrome type. Despite equal familiarity with jaundice and chest pain, the performance of the self-explanation group (but not of the non-self-explanation group) on jaundice cases significantly improved between training and assessment phases (p = 0.035) whereas no differences between phases emerged on chest pain cases. Self-explanation of pathophysiology did not improve students’ diagnostic performance for all diseases. Apparently, the positive effect of this form of self-explanation on performance depends on the studied diseases sharing similar pathophysiological mechanisms, such as in the jaundice cases.

The effect of self-explanation of pathophysiological mechanisms of diseases on medical students' diagnostic performance.

Self-explanation while diagnosing clinical cases fosters medical students' diagnostic performance. In previous studies on self-explanation, students were free to self-explain any aspect of the case, and mostly clinical knowledge was used. Elaboration on knowledge of pathophysiological mechanisms of diseases has been largely unexplored in studies of strategies for teaching clinical reasoning. The purpose of this two-phase experiment was to investigate the effect of self-explanation of pathophysiology during practice with clinical cases on students' diagnostic performance. In the training phase, 39 4th-year medical students were randomly assigned to solve 6 criterion cases (3 of jaundice; 3 of chest pain), either self-explaining the pathophysiological mechanisms of the findings (n=20) or without self-explaining (n=19). One-week later, in the assessment phase, all students solved 6 new cases of the same syndromes. A repeated-measures analysis of variance on the mean diagnostic accuracy scores showed no significant main effects of study phase (p=0.34) and experimental condition (p=0.10) and no interaction effect (p=0.42). A post hoc analysis found a significant interaction (p=0.022) between study phase and syndrome type. Despite equal familiarity with jaundice and chest pain, the performance of the self-explanation group (but not of the non-self-explanation group) on jaundice cases significantly improved between training and assessment phases (p=0.035) whereas no differences between phases emerged on chest pain cases. Self-explanation of pathophysiology did not improve students' diagnostic performance for all diseases. Apparently, the positive effect of this form of self-explanation on performance depends on the studied diseases sharing similar pathophysiological mechanisms, such as in the jaundice cases.

Food sharing in vampire bats: reciprocal help predicts donations more than relatedness or harassment

Common vampire bats often regurgitate food to roost-mates that fail to feed. The original explanation for this costly helping behaviour invoked both direct and indirect fitness benefits. Several authors have since suggested that food sharing is maintained solely by indirect fitness because non-kin food sharing could have resulted from kin recognition errors, indiscriminate altruism within groups, or harassment. To test these alternatives, we examined predictors of food-sharing decisions under controlled conditions of mixed relatedness and equal familiarity. Over a 2 year period, we individually fasted 20 vampire bats (Desmodus rotundus) and induced food sharing on 48 days. Surprisingly, donors initiated food sharing more often than recipients, which is inconsistent with harassment. Food received was the best predictor of food given across dyads, and 8.5 times more important than relatedness. Sixty-four per cent of sharing dyads were unrelated, approaching the 67 per cent expected if nepotism was absent. Consistent with social bonding, the food-sharing network was consistent and correlated with mutual allogrooming. Together with past work, these findings support the hypothesis that food sharing in vampire bats provides mutual direct fitness benefits, and is not explained solely by kin selection or harassment.

Can Personality Disorder Experts RecognizeDSM-IVPersonality Disorders From Five-Factor Model Descriptions of Patient Cases?

Dimensional models of personality are under consideration for integration into the next Diagnostic and Statistical Manual of Mental Disorders (DSM-5), but the clinical utility of such models is unclear. To test the ability of clinical researchers who specialize in personality disorders to diagnose personality disorders using dimensional assessments and to compare those researchers' ratings of clinical utility for a dimensional system versus for the DSM-IV. A sample of 73 researchers who had each published at least 3 (median = 15) articles on personality disorders participated between December 2008 and January 2009. The Five-Factor Model (FFM), one of the most-studied dimensional models to date, was compared to the DSM-IV. Participants provided diagnoses for case profiles in DSM-IV and FFM formats and then rated the DSM-IV and FFM on 6 aspects of clinical utility. Overall, participants had difficulty identifying correct diagnoses from FFM profiles (t₇₂ = 12.36, P < .01), and the same held true for a subset reporting equal familiarity with the DSM-IV and FFM (t₂₃ = 6.96, P < .01). Participants rated the FFM as less clinically useful than the DSM for making prognoses, devising treatment plans, and communicating with professionals (all t₆₉ > 2.19, all P < .05), but more useful for communicating with patients (t₆₉ = 3.03, P < .01). The results suggest that personality disorder expertise and familiarity with the FFM are insufficient to correctly diagnose personality disorders using FFM profiles. Because of ambiguity inherent in FFM profile descriptors, this insufficiency may prove unlikely to be attenuated with increased clinical familiarity with the FFM.

The Genetic Basis of Individual-Recognition Signals in the Mouse

The major histocompatibility complex (MHC) is widely assumed to be a primary determinant of individual-recognition scents in many vertebrates [1-6], but there has been no functional test of this in animals with normal levels of genetic variation. Mice have evolved another polygenic and highly polymorphic set of proteins for scent communication, the major urinary proteins (MUPs) [7-12], which may provide a more reliable identity signature ([13, 14] and A.L. Sherborne, M.D.T., S. Paterson, F.J., W.E.R.O., P. Stockley, R.J.B., and J.L.H., unpublished data). We used female preference for males that countermark competitor male scents [15-17] to test the ability of wild-derived mice to recognize individual males differing in MHC or MUP type on a variable genetic background. Differences in MHC type were not used for individual recognition. Instead, recognition depended on a difference in MUP type, regardless of other genetic differences between individuals. Recognition also required scent contact, consistent with detection of involatile components through the vomeronasal system [6, 18]. Other differences in individual scent stimulated investigation but did not result in individual recognition. Contrary to untested assumptions of a vertebrate-wide mechanism based largely on MHC variation, mice use a species-specific [12] individual identity signature that can be recognized reliably despite the complex internal and external factors that influence scents [2]. Specific signals for genetic identity recognition in other species now need to be investigated.

Greek Myths, Christian Mysteries, and the Tautegorical Symbol

Anyone who has attended an academic conference will be able to sympathize with the audience of the lecture delivered at the Royal Society of Literature on May 18, 1825. What the members of the society heard that day, a lecture announced and eventually published under the title the Prometheus of Aeschylus, not only lasted an hour and twenty-five minutes but never referred to a single line of Aeschylus's play and consisted largely of assertions such as the following, in which the liberal admixture of Greek and Latin terms is representative: sum, stated in the terms of philosophic logic, is this: First, what Moses appropriated to the chaos itself: what Moses made passive and a materia subjecta et lucis et tenebrarum [underlying matter of both light and dark], the containing prothemenon (1) [something posited before] of the thesis and antithesis; this the Greek placed anterior to the chaos: the chaos itself being the struggle between the hyperchronia, the ideai pronomoi [ideas prior to law] as the unevolved unproduced prothesis of which idea kai nomos (idea and law), are the thesis and antithesis (I use the word 'produced' in the mathematical sense, as a point elongating itself to a bipolar line) (Shorter Works and Fragments [1995], 1273). The following day the lecturer himself expressed, in a letter to his nephew, remorseful Sympathy with the Audience, who could not possibly understand the 10th part--For let its merits be what they may, it was not a thing to read, but to be read (Collected Letters [1956-71], 5:461). At the risk of anticlimax I shall reveal that the lecturer was Samuel Taylor Coleridge, and the occasion of the lecture his election to the Royal Society of Literature. Although membership entailed an obligation to address the society every year, that requirement was evidently waived in Coleridge's case, for he delivered no successor to his inaugural lecture. It is understandable that someone who had reason to be anxious about his reputation should have wanted to impress a distinguished audience with his erudition. It is also likely, as Anthony Harding has concluded (The Reception of Myth in English Romanticism [1995], 248-50), that Coleridge sought to ingratiate himself with that audience, consisting as it would have of precisely the educated upper class to whom he had sought to address himself in his lay sermons of 1816-17, in the hope of fostering the development of what he called the clerisy, a class of people who would provide intellectual and moral leadership for the nation. Both Coleridge's subject and his hermetic presentation of it were consistent with this broader ideological aim, which he would propound explicitly in On the Constitution of the Church and State (1830). With its complicated syntax, recondite scholarly references, frequent use of un-translated Greek and Latin, and casual assumption of the listeners' equal familiarity with the Bible, Greek mythology, and ancient mystery religions, Coleridge's lecture in effect sought to perform the very function that it attributed to Aeschylus's play, that of conveying a profound religious truth to a select few while disguising it from the multitude. If the secret doctrines of the had to be protected from the debasing influences of polytheism in ancient Athens (1277), then those same doctrines had to be protected from materialism and Palyean natural theology in modern London. What were those doctrines? A passage Coleridge incorporated into his lecture from the 1818 edition of his miscellany The Friend summarizes his conviction that the Greek mystery cults, guided by divine providence, communicated a philosophically inflected form of Mosaic monotheism and thereby protected the Greeks from the worst effects of their popular religion: earliest Greeks took up the religious and lyrical poetry of the Hebrews; and the schools of the prophets were, however partially and imperfectly, represented by the mysteries derived through the corrupt channel of the Phoenicians. …

Communicative factors in speech variation: Hyperarticulatory compensation for lexical competition

Based on factors in lexical competition such as usage frequency and similarity-neighborhood density, previous research has characterized words as ‘‘easy’’ or ‘‘hard’’ to identify. Lindblom [in W. Hardcastle and A. Marchal (Eds.), 403–439 (1990)] has proposed that talkers accommodate listeners’ communicative needs by controlling the degree of reduction (hyper- and hypoarticulation) in different contextual conditions. This study examines the degree of centralization of vowels in 38 ‘‘easy’’ and 38 ‘‘hard’’ monosyllabic (CVC) words of equal familiarity spoken in isolation by ten talkers. Measurements of the first two vowel formants (F1, F2) are made at the point of maximal displacement in the vowel (excluding the initial and final 50 ms of the vowel). Centralization is measured by calculating the Euclidean distance from the center of a talker’s F1–F2 vowel space. Three results emerge: (1) overall ‘‘easy’’ words were significantly more centralized than ‘‘hard’’ words; (2) peripheral vowels, such as /i/, /a/, /u/, showed the greatest effect; and (3) there was considerable between-talker variability both in overall vowel centralization and in the magnitude of the difference between vowels in ‘‘easy’’ and ‘‘hard’’ words. [Work supported by NIH Grant No. DC00012.]

The Hon. Daines Barrington, F. R. S. —annotations on two journals compiled by Gilbert White

In the field of natural history the Hon. Daines Barrington (1727—1800) is best known as one of the correspondents to whom Gilbert White addressed many of the letters that comprise The Natural History of Selhorne (1). Of almost equal familiarity is the knowledge that Barrington devised the format of The Naturalist's Journal (2), in copies of which White recorded near daily observations of weather and other natural occurrences for a period of over 25 years. That the putative correspondence of Selborne was based on a real correspondence (3), and that Barrington arranged for four of White’s dissertations (4), on ‘hirundines’, to be read at meetings of the Royal Society (5), is also well known. What, however, as the result of recent research, can now be reported for the first time, is that Barrington’s contribution to White’s work extends a good deal further than has been previously thought; and that, with William Sheffield (6), he provided White with the incentive both to ‘quicken [his] Industry, &amp; sharpen [his] attention’ (7)—two important acknowledgements for a man who, throughout his life, experienced a degree of isolation (8), and who, as an old man, in response to a correspondent who complained ‘a little of Procrastination’ , claimed:

Analysis of Wisc Coding: 4. Paired-Associate Learning and Performance Strategies

A training procedure was used to ensure equal familiarity with the number-symbol pairs of the code of the WISC for both good and poor coders. The former learned more readily than the latter, but subsequent scores on the coding task were equivalent for both groups when account was taken of differences in writing speed. Two possible sources of slower performance were investigated: time taken to refer to the code and time spent scanning completed work. These were not found to be related to poor coding performance. It was concluded that learning of the paired-associates and writing speed discriminated between good and poor coders.

Auditory word recognition as a function of meaningfulness, abstractness and phonetic structure

Sixty one-syllable words of equal familiarity level were presented aurally under conditions of masking noise. Auditory word recognition was found to be a function of meaningfulness and abstractness (defined as related to sense experience). The relationship between recognition and abstractness (defined as a generic-specific dimension) was not significant. Results indicated that the initial phoneme of a word is an important determinant of word recognition. A phonemic hierarchy was established and shown to relate to hierarchies obtained under different experimental conditions.

EFFECTS OF MODE RESPONSE AND SEX OF E UPON RECOGNITION THRESHOLDS OF TABOO WORDS.

Two experiments (40 male Ss, and 40 female Ss) investigated the effects of mode of response (written or oral) and sex of E upon recognition thresholds of taboo and neutral words. Words were selected on the basis of taboo ratings by 81 students (42 men, 39 women) and familiarity ratings by 44 men and 34 women. Each of the five most taboo words was matched with a neutral word of equal familiarity. Each word was presented tachistoscopically for .01 sec. with constant illumination for 10 trials. Ss either said or wrote words as they were recognized. Women showed no differences in thresholds for taboo and neutral words. Men had a significantly higher threshold for spoken taboo words than for written ones. Sex of E had no effect. There was no evidence for a general defensive reaction to taboo words.