RESUMEN

Previous studies on human cognition show that people with different cultural backgrounds may differ in various ways. However, there are other unexplored possibilities for cultural differences including degree of handedness thought to reflect hemispheric coordination, reliance on verbal versus visual representation in problem solving, and working memory capacity both spatial and operational. We assessed each of these using the Edinburgh scale, a validated scale of style of processing, and two automatic working memory span tasks. Participants were either native Chinese students (who spoke Mandarin) or American students. Data showed that culture impacted the set of measures but gender did not and these factors did not interact. Chinese and American students showed the largest difference in their operational working memory. We also examined the pattern of correlations among the measures across the two groups and found differences due to cultural group as well.

RESUMEN

Virtual reality (VR) technology has become increasingly prevalent in our society and has been used for a myriad of applications ranging from psychotherapy to training members of the military. However, one issue that arises from the use of VR is motion sickness, thus making predictors and indicators of motion sickness desirable. To date, a number of indicators of motion sickness have been derived based on nonlinear characteristics of human motion recorded using motion capture systems. While it is known that nonlinear measures can be used to predict motion sickness, it is not known whether people are perceptually sensitive to these particular nonlinear parameters. The aims of this study included establishing whether individuals consistently sort phase plots of sick and well individuals' postural motion without being explicitly told to do so; determining what nonlinear movement parameters could be used to represent these judgments; and assessing the stability of nonlinear measures found to be successful at predicting motion sickness by Smart et al. (2014). Through two methods of analysis (perceptual and quantitative), this research demonstrated that participants can indeed sort the graphic depictions of sick and well participants' postural motion and seem to be perceptually sensitive to nonlinear parameters (normalized path length, path length, elliptical area) that are known to be predictive of motion sickness.

RESUMEN

Previous research using the change detection task has found little or no relationship between P3 amplitude and working memory load. This contrasts with findings from other paradigms that indicate a decrease in P3 amplitude with increases in working memory load. We adopted a principal component analysis strategy to resolve this discrepancy. After ERPs were decomposed, the P3 component decreased in amplitude when the memory load increased. Its amplitude was also associated with individuals' working memory capacity. In conclusion, P3 plays a critical role in change detection task as it does in other working memory tasks.

Asunto(s)

RESUMEN

We offer a minor technical correction to the published proof of part (ii) of the main theorem in Silbert and Thomas (Psychonomic Bulletin & Review, 20, 1-20, 2013) that somewhat limits the scope of the equivalence observed in that work. Specifically, in order for a mean shift integrality with decisional separability to be mimicked by a perceptually separable but nondecisionally separable configuration, one needs to assume stimulus invariance. This holds when all of the covariance matrices in the stimulus configuration are equal to each other. We note that part (i) of the theorem is unaffected by this modification; an empirical finding of perceptual separability and the failure of decisional separability can be mimicked by a perceptually nonseparable, decisionally separable configuration without restricting the covariance matrices to be equal. We also note that stimulus invariance is often assumed in simple designs (e.g., Macmillan & Ornstein in Journal of the Acoustical Society of America, 97, 1261-1285, 1998), due to the implausibility of different perceptual correlations being present within stimuli perched very closely in perceptual space.

Asunto(s)

RESUMEN

Recent work in the general recognition theory (GRT) framework indicates that there are serious problems with some of the inferential machinery designed to detect perceptual and decisional interactions in multidimensional identification and categorization (Mack, Richler, Gauthier, & Palmeri, 2011). These problems are more extensive than previously recognized, as we show through new analytic and simulation-based results indicating that failure of decisional separability is not identifiable in the Gaussian GRT model with either of two common response selection models. We also describe previously unnoticed formal implicational relationships between seemingly distinct tests of perceptual and decisional interactions. Augmenting these formal results with further simulations, we show that tests based on marginal signal detection parameters produce unacceptably high rates of incorrect statistical significance. We conclude by discussing the scope of the implications of these results, and we offer a brief sketch of a new set of recommendations for testing relationships between dimensions in perception and response selection in the full-factorial identification paradigm.

Asunto(s)

RESUMEN

Poor performance in pressure-filled situations, or "choking under pressure," has largely been explained by two different classes of theories. Distraction theories propose that choking occurs because attention needed to perform the task at hand is coopted by task-irrelevant thoughts and worries. Explicit monitoring theories claim essentially the opposite-that pressure prompts individuals to attend closely to skill processes in a manner that disrupts execution. Although both mechanisms have been shown to occur in certain contexts, it is unclear when distraction and/or explicit monitoring will ultimately impact performance. The authors propose that aspects of the pressure situation itself can lead to distraction and/or explicit monitoring, differentially harming skills that rely more or less on working memory and attentional control. In Experiments 1-2, it is shown that pressure that induces distraction (involving performance-contingent outcomes) hurts rule-based category learning heavily dependent on attentional control. In contrast, pressure that induces explicit monitoring of performance (monitoring by others) hurts information-integration category learning thought to run best without heavy demands on working memory and attentional control. In Experiment 3, the authors leverage knowledge about how specific types of pressure impact performance to design interventions to eliminate choking. Finally, in Experiment 4, the selective effects of monitoring-pressure are replicated in a different procedural-based task: the serial reaction time task. Skill failure (and success) depends in part on how the performance environment influences attention and the extent to which skill execution depends on explicit attentional control.

Asunto(s)

RESUMEN

The current study adapted the Garner paradigm for diagnosing separable versus integral perceptual dimensions to the eye-blink classical conditioning paradigm using rabbits. Specifically, this study examined the ability of rabbits to categorize stimuli based on one auditory dimension while ignoring a second, irrelevant dimension by displaying an appropriate eye-blink for bilaterally conditioned discriminative responses. Tones used in training varied along two dimensions, starting frequency and magnitude of frequency sweep upwards from the start. Rabbits first learned to categorize along a single dimension (blinking one eye for one category response and the other eye for the other response) and then continued to categorize tones in a second phase in which the irrelevant dimension was varied. The variation of the irrelevant dimension did not disrupt performance, indicating that rabbits perceive these dimensions as separable.

Asunto(s)

RESUMEN

In DeCaro et al. [DeCaro, M. S., Thomas, R. D., & Beilock, S. L. (2008). Individual differences in category learning: Sometimes less working memory capacity is better than more. Cognition, 107, 284-294] we demonstrated that sometimes less working memory (WM) has its advantages. The lower individuals' WM, the faster they achieved success on an information-integration (II) category learning task adopted from Waldron and Ashby [Waldron, E. M., & Ashby, F. G. (2001). The effects of concurrent task interference on category learning: Evidence for multiple category learning systems. Psychonomic Bulletin & Review, 8, 168-176]. We attributed this success to the inability of lower WM individuals to employ explicit learning strategies heavily reliant on executive control. This in turn, we hypothesized, might push lower WM individuals to readily adopt procedural-based strategies thought to lead to success on the II task. Tharp and Pickering [Tharp, I. J., & Pickering, A. D. (2009). A note on DeCaro, Thomas, and Beilock (2008): Further data demonstrate complexities in the assessment of information-integration category learning. Cognition] recently questioned whether the II category learning task DeCaro et al. used really reflects procedural learning. In an effort to investigate Tharp and Pickering's assertions with respect to individual differences in WM, we replicate and extend our previous work, in part by modeling participants' response strategies during learning. We once again reveal that lower WM individuals demonstrate earlier II learning than their higher WM counterparts. However, we also show that low WM individuals' initial success is not because of procedural-based responding. Instead, individuals lower in WM capacity perseverate in using simple rule-based strategies that circumvent heavy demands on WM while producing above-chance accuracy.

Asunto(s)

RESUMEN

Kingston, Diehl, Kirk, and Castleman (Journal of Phonetics, 2008) present a sophisticated experimental design and detection theoretic analysis of the internal auditory structure of phonological contrasts. However, a potentially important aspect of multidimensional detection theory - the covariance structure of assumed underlying multivariate Gaussian perceptual densities - was left unexplored. We discuss Kingston, et al.'s approach in the context of a general definition of multidimensional d' and present a description of two distinct configurations of perceptual densities requiring fundamentally different interpretations that account equally well for the "mean-shift integrality" results reported by Kingston, et al. We end with a brief discussion of approaches to distinguishing these underlying configurations empirically.

RESUMEN

Work on visual perceptual learning for contrast detection has shown that reliable decreases in detection thresholds are accompanied by reliable increases in false alarm rates (Wenger & Rasche, 2006). The present study assesses the robustness and replicability of these changes, demonstrating that they are independent of a variety of task demands (i.e., the specific method used for perceptual practice and threshold estimation) and the presence or absence of trial-by-trial feedback and that the source of the increases can be found in shifts in changes in sensitivity and in bias for detection, identification, or both. Although the increase in false alarm rates suggests a strategic shift in response criteria for detection, we demonstrate that there are multiple potential explanations, including explanations that do not require strategic shifts on the part of the observer. The empirical evidence and analysis of alternative explanations reinforce the inference that visual perceptual learning may involve more than changes in perceptual sensitivity and that cortical circuits beyond the primary visual areas may be involved.

Asunto(s)

RESUMEN

BACKGROUND: Preliminary research with the Categorization Program (CP) indicated that this therapeutic modality is beneficial in improving cognitive abilities in survivors of moderate-to-severe traumatic brain injury (TBI). This study provides additional evidence for the use of the CP in postacute TBI cognitive rehabilitation. METHODS: Twenty-one participants in the experimental group received the CP training, and 14 participants in the control group received the conventional treatment used at their rehabilitation center. Following neuropsychological testing, participants began their therapy program. RESULTS: There was no significant difference in the baseline performance of the 2 TBI groups on any of the measures. CP-dependent measures correlated significantly with several neuropsychological tests. Both groups improved in their neuropsychological test performance and on functional outcomes tests. However, subjects in the experimental group improved on more tests than participants in the control group. Posttest performance of subjects in the TBI control group was significantly lower on the CP Test 1 and CP Test 2 as compared with the experimental group. Furthermore, the performance of participants in the CP group improved across the 3 probe tasks demonstrating generalizability to new tasks; the performance of participants in the control group did not improve. CONCLUSIONS: The CP is an effective therapy method to reduce categorization impairment and improve cognitive performance of survivors of TBI who are enrolled in postacute rehabilitation. This study contributes to the growing body of evidence supporting cognitive rehabilitation efforts after TBI.

Asunto(s)

RESUMEN

We examined whether individual differences in working memory influence the facility with which individuals learn new categories. Participants learned two different types of category structures: rule-based and information-integration. Successful learning of the former category structure is thought to be based on explicit hypothesis testing that relies heavily on working memory. Successful learning of the latter category structure is believed to be driven by procedural learning processes that operate largely outside of conscious control. Consistent with a widespread literature touting the positive benefits of working memory and attentional control, the higher one's working memory, the fewer trials one took to learn rule-based categories. The opposite occurred for information-integration categories - the lower one's working memory, the fewer trials one took to learn this category structure. Thus, the positive relation commonly seen between individual differences in working memory and performance can not only be absent, but reversed. As such, a comprehensive understanding of skill learning - and category learning in particular - requires considering the demands of the tasks being performed and the cognitive abilities of the performer.

Asunto(s)

RESUMEN

The present research provides evidence that people use facial prototypes when they encounter different names. In Experiment 1, participants created face exemplars for fifteen common male names, subsets of which were endorsed as good examples by a second set of participants. These most typical faces were morphed to create face-name prototypes. In Experiment 2, participants matched one of the names to each of the prototype faces from Experiment 1. Participants' matching choices showed convergence in naming the prototypes for many of the names. Experiment 3 utilized these same prototypes in a learning task designed to investigate if the face-name associations revealed in Experiment 2 impacted the learnability of the names. Participants learned face-name pairings that had a higher association (based on frequencies from Experiment 2) faster than pairings with a low association. Results suggest a more direct relationship between faces and names than has been previously proposed.

Asunto(s)

RESUMEN

BACKGROUND: Previous research suggests that traumatic brain injury (TBI) interferes with the ability to extract and use attributes to describe objects. This study explored the effects of a systematic Categorization Program (CP) in participants with TBI and noninjured controls. PARTICIPANTS: Ten persons with moderate to severe TBI who received comprehensive postacute rehabilitation services and 13 matched noninjured controls participated in the study. INTERVENTION: All participants received CP training for 3 to 5 hours per week for 10 to 12 weeks that consisted of 8 levels and targeted concept formation, object categorization, and decision-making abilities. MAIN OUTCOME MEASURES: The Mayo-Portland Adaptability Inventory-3 (MPAI-3) and the Community Integration Questionnaire (CIQ). Two Categorization Tests (administered pretraining and posttraining) and 3 Probe Tasks (administered at specified intervals during training) assessed skills relating to categorization. RESULTS: Both groups showed significant improvement in categorization performance after the CP training on the 2 Categorization Tests related to the CP. They also were able to generalize and apply categorization and sorting skills in new situations (as measured by the Probe Tasks). Participants with TBI had improved functional outcome performance measured by the MPAI-3 and the CIQ. CONCLUSIONS: The systematic and hierarchical structure of the CP is beneficial to participants with TBI during postacute rehabilitation. This study contributes to the growing body of evidence supporting cognitive rehabilitation after moderate to severe TBI.

Asunto(s)