Is Speech Arrest during Wada Testing a Valid Method for Determining Hemispheric Representation of Language?

Background and objective: The intracarotid amobarbital procedure, or Wada test, is the method of choice to determine hemispheric representation of language, and is routinely used in the presurgical evaluation for intractable epilepsy. Some investigators perform comprehensive language assessments, but others base language lateralization solely on speech arrest. This study sought to determine whether speech arrest alone during Wada testing provides valid data regarding language lateralization. Methods: The subjects (previously reported) were 21 patients evaluated for intractable epilepsy, who underwent language lateralization by Wada testing and functional MRI (FMRI). For each patient, language representation was determined by calculating: (1) a Wada laterality index based exclusively on speech arrest; (2) a Wada laterality index based on comprehensive language assessment; and (3) an FMRI laterality quotient. Correlation coefficients and categorical classifications were analyzed. Results: There was no significant correlation between the Wada laterality quotient derived from duration of speech arrest and either the comprehensive Wada language laterality score (r= .35,p= .12) or FMRI language laterality score (r= .32,p= .16). Categorical classification as left, right or bilateral language also showed marked discordance between speech arrest and the other two methods. Conclusion: Duration of speech arrest during Wada testing is not a valid measure of language dominance.     

Professional ethics of psychologists and physicians: morality, confidentiality, and sexuality in Israel

Clinical psychologists' and nonpsychiatric physicians' attitudes and behaviors in sexual and confidentiality boundary violations were examined. The 171 participants' responses were analyzed by profession, sex, and status (student, resident, professional) on semantic differential, boundary violation vignettes, and a version of Pope, Tabachnick, and Keith-Spiegel's (1987) ethical scale. Psychologists rated sexual boundary violation as more unethical than did physicians (p less than .001). Rationale (p less than .01) and timing (p less than .0001) influenced ratings. Psychologists reported fewer sexualized behaviors than physicians (p less than .05). Professional experience (p less than .01) and sex (p less than .05) were associated with confidence-violating behavior. Overall, 78% of the sample reported attitudes or behaviors associated with boundary violations. The behavior violations were correlated (r = .49). Actual violators rated vignette violators more leniently than did nonviolators (p less than .01).     

Introduction and overview: Global information ethics

This is an introduction to a set of papers on Computer Ethics from the conference ETHICOMP95. Taken as a whole, the collection of papers provides arguments and concepts to launch a new development in computer ethics: ‘Global Information Ethics’. A rationale for globalization is provided, as well as some early efforts which move in that direction. ETHICOMP95, an international conference on Computer Ethics, was held 28–30 March 1995 at De Montfort University, Leicester, UK. Co-directors were Terrell Ward Bynum and Simon Rogerson.     

Recall of rapidly presented random chess positions is a function of skill

A widely cited result asserts that experts’ superiority over novices in recalling meaningful material from their domain of expertise vanishes when they are confronted with random material. A review of recent chess experiments in which random positions served as control material (presentation time between 3 and 10 sec) shows, however, that strong players generally maintain some superiority over weak players even with random positions, although the relative difference between skill levels is much smaller than with game positions. The implications of this finding for expertise in chess are discussed and the question of the recall of random material in other domains is raised.     

A critical review of theS/L reliability index

The meaning and properties of a commonly used index of reliability, S/L,were examined critically. It was found that the index does not reflect any conventional concept of reliability. When used for an identical behavioral observation session, it is not statistically correlated with other reliability indices. Within an observation session, the standardizing measure of Lis beyond the control of the investigator. Furthermore, the reason for the choice of Las the standard is unclear. The role of chance agreement in S/Lis not known. The exact interpretation of the index depends on which observer reports L.Overall the conceptual and mathematical meaning of S/Lis dubious. It is suggested that the S/Lindex should not be used until its nature is shown to be a measure of reliability. Other approaches such as the intraclass correlations and generalizability coefficients should be used instead.The authors are indebted to Johnny Matson for his critique of an earlier version of this paper.     

REM motivation induced by brief REM deprivation: the influence of cognition, gender, and personality.

Prominence of the brain's right-hemisphere information processing and intensity of dream experience are two theoretically related constructs that have been proposed as important psychological aspects of REM sleep. Either view is consistent with the prediction that the effect of REM deprivation will depend in part on the nature of cognitive activity that is initiated at the onset of each REM period and that "substitutes" for the interrupted REM process. In the present study, the effect of REM deprivation was more striking for female subjects given a digits task than for female subjects given a fantasy-reporting task during awakening used to induce REM deprivation for the first 6 hours of the night. High neuroticism appeared to exaggerate the effect. No corresponding pattern was observed for the male subjects. These preliminary finding may be exaggerated by cognitive activity that is functionally incongruent with those processes. The results also raise interesting questions about individual differences.     

Children's responses to stories with male and female characters

The sex of the main character was varied in six children's stories which were then read by fourth, sixth and eighth graders. The children answered four questions about the stories. Both boys and girls responded more positively to the questions “Would you like to be (character's name?)” and “Would you like to do the things (character's name) did?” when the main character was a male. Boys preferred stories about males, and this preference increased with grade level. A preference for stories about females was marginally significant only for the older girls. Theoretical and practical implications are discussed.     

Effect of compatibility of S-R mapping on reactions toward the stimulus source

This research was concerned with separating the effects of three varieties of S-R compatibility: reactions toward the stimulus source, compatibility of S-R mapping, and display-control arrangement correspondence. In experiments 1 and 2, subjects pressed a green or red key located on the left and right in response to the onset of a green or red stimulus presented in a left or right window. Half of the subjects pressed the key which corresponded to the color of the stimulus (compatible S-R mapping) while the other half pressed the alternate colored key (incompatible S-R mapping). In the compatible mapping task, reactions were faster when location of stimulus and response corresponded than when they did not while, in the incompatible task, reactions were faster when location of stimulus and response did not correspond. This apparent reversal in the tendency to react toward the stimulus source was attributed to display- control arrangement correspondence rather than to logical recoding of the directional cue. Experiment 3 established that faster reactions toward the stimulus source occured only under compatible mapping instructions.