Stereotype threat and inflexible perseverance in problem solving

The present research examines whether women burdened by stereotype threat, a threat of confirming negative ingroup stereotypes (Steele, C. M., & Aronson, J. (1995). Stereotype threat and the intellectual test performance of African Americans. Journal of Personality and Social Psychology, 69(5), 797-811), are less able to abandon old strategies and employ newer, more efficient ones when conditions change. In two studies, stereotype threat was found to increase inflexible perseverance: women made to believe they were taking a diagnostic math/spatial ability test, compared to those not threatened by stereotypes, were more likely to use previously successful but presently inefficient or incorrect strategies. In Study 1, participants under stereotype threat also suppressed relevant stereotypes to the greatest degree, and their inflexible perseverance was predicted by the degree to which they suppressed these stereotypes. Implications for test performance and potential decision-making effects of stereotype threat are discussed.     

A choice reaction time index of callosal anatomical homotopy

Tachistoscopically presented bilateral stimulus pairs not parallel to the meridian produced significantly longer RTs on a task requiring discrimination of shapes (Go/no-Go) than pairs emplaced symmetrically on each side of the meridian in Desjardins and Braun [Desjardins, S., & Braun, C. M. J. (2006). Homotopy and heterotopy and the bilateral field advantage in the Dimond paradigm. Acta Psychologica, 121,  125–136]. This was explained by the fact that there are more homotopic than heterotopic fibers in the corpus callosum. However: (1) different parts of the visual field were not equiprobably stimulated, possibly causing subtle biases, (2) the predicted cost of vertical asymmetry was tested only with bilateral stimuli, and (3) interstimulus distance was at the outer limit of callosal midline fusion (10.6°). Here, a tachistoscopic experiment with 24 normal participants replicated the between-field vertical symmetry advantage [Desjardins, S., & Braun, C. M. J. (2006). Homotopy and heterotopy and the bilateral field advantage in the Dimond paradigm. Acta Psychologica, 121, 125–136.], but without irrelevant stimulation conditions and with more proximal stimuli. In addition, a significant specific cost of vertical asymmetry of 7 ms was found for between-field integration over within-field integration. As far as we know, this is the first demonstration of an effect of callosal anatomical homotopy with reaction time.     

Reviews: Books, Art

YOGA AND PSYCHOLOGY. By Howard Coward. 115 pp. Albany: State University of New York Press, 2002. $16.95. CASE STUDIES IN INFANT MENTAL HEALTH: RISK, RESILIENCY AND RELATIONSHIPS. Edited by Joan J. Shirilla and Deborah J. Weatherston. 203 pp. Washington, D.C.: Zero to Three, 2002. $32.95. JACOB'S SHADOW: CHRISTIAN PERSPECTIVES ON MASCULINITY. By Herbert Anderson. 173 pp. Louisville, KY: Bridge Resources, 2002. $18.95. LEONARDO DA VINCI. By Sherwin B. Nuland. 170 pp. New York: Viking, 2002. $19.95. FAITH AND THE PLACEBO EFFECT: AN ARGUMENT FOR SELF-HEALING. By Lolette Kuby. 323 pp. Novato, CA: Origin Press, 2001. $23.00. NOTHING PERSONAL, JUST BUSINESS: A GUIDED JOURNEY INTO ORGANIZATIONAL DARKNESS. By Howard F. Stein. Westport, CT: Quorum/Greenwood Publishing Group, 2001. FAITH BEYOND FAITH HEALING: FINDING HOPE AFTER SHATTERED DREAMS. By Kimberly Winston. 115 pp. Brewster, MA: Praraclete Press, 2002. A SHADOW OF GLORY: READING THE NEW TESTAMENT AFTER THE HOLOCAUST. Edited by Tod Linafelt. New York and London: Routledge, 2002. LOVE IS STRONGER THAN DEATH: THE MYSTICAL UNION OF TWO SOULS. By Cynthia Bourgeault. 222 pp. Great Barrington, MA: Lindisfarne Books, 2001. $14.95. Moving Pictures     

Reaction times as a measure of uncertainty

In this article, a method is presented to analyse relationships between detection or discrimination frequencies and reaction times in psychophysical tasks. It is shown in three empirical data sets that reaction time decreases as a linear function of the absolute value of the logit transforms of the response probabilities. Such a function stresses the characteristic uncertainty associated with subjects' responses and the relation between their response parameters and the response criterion used by the subjects.     

Spatial memory of domestic dogs (Canis familiaris) for hidden objects in a detour task

Spatial memory of domestic dogs (Canis familiaris) for hidden objects was investigated via a visible displacement problem of object permanence with a detour paradigm. Experiment 1 showed that dogs were able to spontaneously locate a disappearing object in a detour situation. In Experiments 2 and 3, dead reckoning and allocentric spatial information were put in conflict. Results revealed that dogs simultaneously encoded both sources of information when they had to bypass an obstacle to locate a hidden object. Experiment 3 also revealed that, over the course of testing, dogs gradually learned to rely predominantly on allocentric cues when the detour involved several reorientations. The current study reveals that spatial memory of dogs for hidden objects in a detour task was guided by flexibility in processing spatial information. Dogs could simultaneously encode dead reckoning and allocentric information to locate a disappearing object and used them hierarchically according to the complexity of the detour they encountered in the environment.     

Speech rate as a sticky switch: a multiple lesion case analysis of mutism and hyperlalia

Though it has long been known on the basis of clinical associations and serendipitous observation that speech rate is related to mood and psychomotor baseline, it is less known that speech rate is also related to libido and to immune function. We make the case for a bipolar phenomenon of "psychic tonus," encompassing all these dimensions. The elated, agitated, libidinal, immunofacilitated, and talkative pole is an "approach" disposition primarily activated by the normal left hemisphere-especially, though not exclusively, its frontal lobe. The dejected, lethargic, delibidinized, immunosuppressed, and mute pole is an "avoidance" disposition primarily activated by the normal right hemisphere-especially, though not exclusively, its frontal lobe. In support of this proposed model, we present new evidence, via meta-analysis of previously published single lesion case reports, of a highly significant association between right hemisphere lesions and non-aphasic hyperlalia, and between left hemisphere lesions and non-aphasic mutism.     

Aging: a switch from automatic to controlled processing of sounds?

In this article, the authors show that aging differentially affects peoples' ability to automatically and voluntarily process auditory information. Young, middle-aged, and older adults matched behaviorally in an auditory discrimination task showed similar patterns of neural activity indexing the voluntary and conscious detection of deviant (i.e., target) stimuli. In contrast, a negative wave indexing automatic processing (the mismatch negativity) was elicited only in young adults for near-threshold stimuli. These results indicate that aging affects the ability to automatically register small changes in a stream of homogeneous stimuli. However, this age-related decline in automatic detection of small change in the auditor environment can be compensated for by top-down controlled processes.     

Neurophysiological evidence for disturbances of conflict processing in patients with schizophrenia

Deficits in cognition are a hallmark of schizophrenia. In the present study, the authors investigated the effects of schizophrenia on the neural correlates of conflict processing in a single-trial version of the Stroop task by using event-related brain potentials. Relative to matched controls, patients with schizophrenia showed increased Stroop interference in response time, but this effect was eliminated when the effect of response slowing was controlled. In controls, conflict processing was associated with a negative wave peaking between 400 and 500 ms (N450) and conflict sustained potential (SP) peaking between 600 and 800 ms after stimulus onset. In patients with schizophrenia, the amplitude of the N450 was significantly attenuated and the conflict SP was absent. These results provide evidence for the existence of altered neural processes associated with conflict processing that may be associated with dysfunction of the anterior cingulate and prefrontal cortex in patients with schizophrenia.