Measurement of visual aftereffects and inferences about binocular mechanisms in human vision

There is conflicting evidence concerning the characteristics of binocular channels in the human visual system with respect to the existence of a 'pure' binocular channel that responds only to simultaneous stimulation of both eyes. Four experiments were conducted to resolve these discrepancies and to evaluate the evidence for the existence of such an exclusive binocular channel. In the first three studies, tilt aftereffects were measured after monocular adaptation. The relative sizes of the direct, interocularly transferred, and binocular aftereffects were not influenced by the configuration of the adapting pattern (experiment 1), or by the eye used for adaptation (experiment 2). There were also consistent interobserver differences in the relative sizes of the aftereffect seen after monocular adaptation (experiment 3). Taken together, these data raise questions about the appropriateness of a monocular adaptation paradigm for evaluating the presence of a pure binocular channel in observers with normal binocular vision. In experiment 4, in which the paradigm of alternating monocular adaptation was used, data were obtained that are consistent with the presence of a pure binocular channel.     

Pharmacological dissociation of memory: anisomycin, a protein synthesis inhibitor, and leupeptin, a protease inhibitor, block different learning tasks

Inhibition of protein synthesis by anisomycin for a short duration impairs memory of a one-trial inhibitory avoidance task in rats. Memory of escape conditioning involving eight trials is disrupted only if the duration of protein synthesis is prolonged by repeated injections. In marked contrast, olfactory memory of rats trained on two odor discriminations is not affected by anisomycin even if the duration of inhibition is prolonged and the number of trials is reduced to a minimum. In previous work, leupeptin, a thiol proteinase inhibitor, was shown to impair olfactory discrimination learning, but left inhibitory and avoidance conditioning intact. Together, these results provide a pharmacological double dissociation of memory, and suggest that the same chemistries, or mixtures of chemistries, may not be involved in all types of memory.     

Electrophysiological evidence for age effects on sensory memory processing of tonal patterns

In older adults, difficulties processing complex auditory scenes, such as speech comprehension in noisy environments, might be due to a specific impairment of temporal processing at early, automatic processing stages involving auditory sensory memory (ASM). Even though age effects on auditory temporal processing have been well-documented, there is a paucity of research on how ASM processing of more complex tone-patterns is altered by age. In the current study, age effects on ASM processing of temporal and frequency aspects of two-tone patterns were investigated using a passive listening protocol. The P1 component, the mismatch negativity (MMN) and the P3a component of event-related brain potentials (ERPs) to tone frequency and temporal pattern deviants were recorded in younger and older adults as a measure of auditory event detection, ASM processing, and attention switching, respectively. MMN was elicited with smaller amplitude to both frequency and temporal deviants in older adults. Furthermore, P3a was elicited only in the younger adults. In conclusion, the smaller MMN amplitude indicates that automatic processing of both frequency and temporal aspects of two-tone patterns is impaired in older adults. The failure to initiate an attention switch, suggested by the absence of P3a, indicates that impaired ASM processing of patterns may lead to less distractibility in older adults. Our results suggest age-related changes in ASM processing of patterns that cannot be explained by an inhibitory deficit.     

Somali Women's Reflections on the Adjustment of Their Children in the United States

Somali women were interviewed regarding their children's adjustment. Qualitative analysis revealed 5 themes: cultural comparisons, concerns about children, parents' loss of disciplinary authority, available support, and the future. The women discussed changes in their children, such as loss of respect and threats to use law enforcement against parents. They also discussed their loss of parental authority and the lack of support from U.S. institutions. Implications for schools and mental health professionals are presented. Se entrevistó a mujeres Somalíes con respecto a la adaptación de sus hijos. Los análisis cualitativos revelaron 5 temas: comparaciones culturales, preocupaciones sobre los niños, la pérdida de autoridad disciplinaria de los padres, apoyo disponible y el futuro. Las mujeres hablaron sobre los cambios en sus hijos, como la pérdida de respeto y las amenazas de usar las fuerzas del orden contra sus padres. También hablaron de la pérdida de su autoridad paterna y la falta de apoyo por parte de las instituciones de los Estados Unidos. Se presentan las implicaciones para escuelas y profesionales de la salud mental.     

Who are you looking at? The influence of face gender on visual attention and memory for own- and other-race faces

Previous research suggests that the own-race bias (ORB) in memory for faces is a result of other-race faces receiving less visual attention at encoding. As women typically display an own-gender bias in memory for faces and men do not, we investigated whether face gender and sex of viewer influenced visual attention and memory for own- and other-race faces, and if preferential viewing of own-race faces contributed to the ORB in memory. Participants viewed pairs of female or male own- and other-race faces while their viewing time was recorded. Afterwards, they completed a surprise memory test. We found that (1) other-race males received the initial focus of attention, (2) own-race faces were viewed longer than other-race faces over time, although the difference was larger for female faces, and (3) even though longer viewing time increased the probability of remembering a face, it did not explain the magnified ORB in memory for female faces. Importantly, these findings highlight that face gender moderates attentional responses to and memory for own- and other-race faces.     

The synergy of working memory and inhibitory control: behavioral, pharmacological and neural functional evidences

Concomitant deficits in working memory and behavioral inhibition in several psychiatric disorders like attention-deficit/hyperactivity disorder, addiction or mania, suggest that common brain mechanisms may underlie their etiologies. Based on the theoretical assumption that a continuum exists between health and mental disorders, we explored the relationship between working memory and inhibition in healthy individuals, through spontaneous inter individual differences in behavior, and tested the hypothesis of a functional link through the fronto-striatal dopaminergic system. Rats were classified into three groups, showing good, intermediate and poor working memory and were compared for their inhibitory abilities. These two functions were simultaneously modulated by a dose-effect of d-amphetamine and in situ hybridization was used to quantify dopaminergic receptor (RD1) mRNAs in prefrontal cortex and striatal areas. A functional relationship between working memory and inhibition abilities was revealed. Both functions were similarly modulated by d-amphetamine according to an inverted-U shaped relationship and depending on initial individual performances. D-amphetamine selectively improved working memory and inhibition of poor and intermediate performers at low doses whereas it impaired both processes in good performers at a higher dose. D1 receptors were less expressed in prelimbic, infralimbic and anterior cingulate cortices of good compared to intermediate and poor performers, whereas no difference was observed between groups in striatal areas. The synergy of working memory and inhibitory abilities, observed in both healthy and psychiatric populations, may originate from endogenous variability in dopaminergic prefrontal cortex activity. Such findings confirm the validity of a dimensional approach, based on the concept of continuity between health and mental disorders for identifying endophenotypes of mental disorders.     

Bias in self-motion perceived speed can enhance episodic memory

Prior experiences of a stimulus facilitate reprocessing of that stimulus on a subsequent occasion. This relative ease and speed with which information is processed is defined as fluency and can constitute a basis for memory judgment. Fluency can also be manipulated on line by perceptual bias (e.g., levels of noise), leading to an increase in recognition for items processed more fluently (e.g., items with less noise). Previous experiments using Remember-Know paradigm have shown an impact of perceptual fluency only on familiarity and not on recollection. Recent episodic memory models have postulated a strong link between episodic memory and spatial processes, especially with egocentric updating (Gomez et al. in Acta Psychol 132(3):221-227, 2009). The present experiment was conducted to determine whether self-motion fluency affects recognition performance and particularly has an impact on "Remember" responses. Thirty participants learned a 4-min path movie and then had to recognize among short paths if they were part of the learned path, followed by a Remember-Know procedure for recognized items. Self-motion fluency was manipulated with the presence of nimble acceleration applied on a small part of the recognition paths. Results show that the presence of a self-motion fluency increases significantly the proportion of remember responses solely on learned paths. This study spotlights for the first time a specific fluency effect on recollection and indicates an implication of egocentric-updating processing in episodic memory retrieval.     

Friend influence over adolescent problem behaviors as a function of relative peer acceptance: to be liked is to be emulated

Friend influence over alcohol intoxication and delinquent behavior was examined as a function of relative peer acceptance in a 3-year study of Swedish youth (N = 184 girls, 145 boys). Participants were in the first year of secondary school (7th grade, M = 11.7 years old) or the first year of high school (10th grade, M = 15.3 years old) at the outset. Friends resembled one another before the friendship; resemblances were even greater after the friendship began. Resemblances continued to grow among those who remained friends one year later, but declined among those whose friendships dissolved. Partners were not equally responsible for increases in similarity. In stable friendships, the more accepted partner exerted greater influence over the less accepted partner, such that the greatest increases in problem behaviors were found among less accepted youth whose friends had higher initial levels of delinquency and alcohol intoxication. Unstable friends resembled random pairs of youth in that more- and less-accepted partners were comparably uninfluential.     

When distance pays off: The role of construal level in spending predictions

Self predictions are often optimistically biased, even for recurrent events. People could generate more realistic predictions by using information about past experiences, however they tend to disregard this cognitive approach. Drawing on Construal Level Theory, we propose that increases in construal level facilitate the use of information from past experience, and thereby increase prediction accuracy. This proposal was tested in two studies examining predictions of personal spending. Consistent with the hypotheses, individuals induced to construe the prediction target at a higher level of abstraction generated more accurate predictions (Study 1) and the effect of increased construal level on prediction was attributable to a greater reliance on past experience (Studies 1 and 2). The findings indicate that high-level construal can sometimes benefit prediction accuracy.     

Consequence Mining

The standard semantic definition of consequence with respect to a selected set X of symbols, in terms of truth preservation under replacement (Bolzano) or reinterpretation (Tarski) of symbols outside X, yields a function mapping X to a consequence relation \(\Rightarrow_X\). We investigate a function going in the other direction, thus extracting the constants of a given consequence relation, and we show that this function (a) retrieves the usual logical constants from the usual logical consequence relations, and (b) is an inverse to—more precisely, forms a Galois connection with—the Bolzano–Tarski function.