Intersensory redundancy facilitates prenatal perceptual learning in bobwhite quail (Colinus virginianus) embryos.

Information presented redundantly and in temporal synchrony across sensory modalities (intersensory redundancy) selectively recruits attention and facilitates perceptual learning in human infants. This comparative study examined whether intersensory redundancy also facilitates perceptual learning prenatally. The authors assessed quail (Colinus virginianus) embryos' ability to learn a maternal call when it was (a) unimodal, (b) concurrent but asynchronous with patterned light, or (c) redundant and synchronous with patterned light. Chicks' preference for the familiar over a novel maternal call was assessed 24 hr following hatching. Chicks receiving redundant, synchronous stimulation as embryos learned the call 4 times faster than those who received unimodal exposure. Chicks who received asynchronous bimodal stimulation showed no evidence of learning. These results provide the first evidence that embryos are sensitive to redundant, bimodal information and that it can facilitate learning during the prenatal period. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A vasopressin metabolite increases attentional selectivity.

Two behavioral paradigms were used to assess the effect of a vasopressin metabolite, AVP4–9, on selectivity of attention. The effects observed in a multiple-cue task indicated that AVP4–9 treatment increased the extent to which attention was controlled by the dominant cues in the environment. When these stimuli predicted reward, the peptide treatment facilitated learning, but when these cues were nonpredictive, the treatment hindered learning. In a redundant learning paradigm, administration of the lower dose of AVP4–9 (1 μg/kg) prevented animals from learning about an added, equally predictive (i.e., redundant) set of cues, suggesting that this treatment caused selective attending to the originally presented stimuli, whose relationship with reward had already been learned. The results of these two studies provide converging evidence that AVP4–9 treatment increases the selectivity of attention, with preferential processing of dominant information. Parallels with the putative attentional effects of increased arousal are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Revising the redundancy principle in multimedia learning.

College students viewed a short multimedia PowerPoint presentation consisting of 16 narrated slides explaining lightning formation (Experiment 1) or 8 narrated slides explaining how a car's braking system works (Experiment 2). Each slide appeared for approximately 8-10 s and contained a diagram along with 1-2 sentences of narration spoken in a female voice. For some students (the redundant group), each slide also contained 2-3 printed words that were identical to the words in the narration, conveyed the main event described in the narration, and were placed next to the corresponding portion of the diagram. For other students (the nonredundant group), no on-screen text was presented. Results showed that the group whose presentation included short redundant phrases within the diagram outperformed the nonredundant group on a subsequent test of retention (d = 0.47 and 0.70, respectively) but not on transfer. Results are explained by R. E. Mayer's (2001, 2005a) cognitive theory of multimedia learning, in which the redundant text served to guide the learner's attention without priming extraneous processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Modeling individual differences in perceptual and attentional processes related to bulimic symptoms.

Attentional and perceptual differences between women with high and low levels of bulimic symptoms were studied with techniques adapted from cognitive science. Stimuli were pictures of young women varying in body size and facial affect. A multidimensional scaling analysis showed that the high symptom women were significantly more attentive to information about body size and significantly less attentive to information about affect. In prototype classification tasks, the high-symptom women used significantly more information about body size and significantly less information about affect. There were strong associations between individual differences in attention in the similarity task and decision making in the classification tasks. The study shows the potential utility of cognitive science methods for the study of cognitive factors in psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive learning in infancy and early childhood.

The stress on genetic factors in early cognitive development has led to the amassing of a considerable body of normative data. However, there has been little interest in determining the scope and complexity of learning possible during the initial phases of development. Research literature and theoretical orientations are presented to show the potential importance of studying early cognitive learning. (201 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Two competing attentional mechanisms in category learning.

This research provides evidence that there are 2 competing attentional mechanisms in category learning. Attentional persistence directs attention to attributes previously found to be predictive, whereas attentional contrast directs attention to attribute values that have not already been associated with a category. Three experiments provided evidence for these mechanisms. Experiments 1 and 2 provided evidence for persistence because increased attention to an attribute followed training in which that attribute was relevant. These experiments also provided evidence for contrast because attention was also increased to the values of an attribute when the values of another, more salient attribute had already been associated with categories. Experiment 3 provided evidence that persistence operates primarily at the level of attributes, whereas contrast operates at the level of attribute values. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention and relative novelty in human perceptual learning.

Four experiments examined the role of attention in human perceptual learning. In Experiment 1, participants were preexposed to a pair of visual (checkerboard) stimuli AX and BX, with common elements X and unique features A and B. A same-different task was then used to assess discrimination of AX and BX and a pair of control stimuli, CY and DY. In addition, participants' eye movements were recorded to assess the role of attentional processes. The results showed that preexposure enhanced discrimination between AX and BX. Furthermore, participants showed greater attention to the preexposed unique features A and B than to the novel unique features C and D, as measured by the eye gaze monitor. Experiments 2 and 3 examined the prediction that perceptual learning is due to the relative familiarity of the common and unique stimulus features. Experiment 4 replicated the intermixed-blocked effect and showed that the way in which AX and BX are presented is also important for perceptual learning. The results generally support the idea that intermixed preexposure to AX and BX increases attention to the unique stimulus features A and B. Some aspects of the results are consistent with a relative novelty account, whereas others implicate a high-level attentional process that is not driven by stimulus novelty. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Long-term abstract learning of attentional set.

How does past experience influence visual search strategy (i.e., attentional set)? Recent reports have shown that, when given the option to use 1 of 2 attentional sets, observers persist with the set previously required in a training phase. Here, 2 related questions are addressed. First, does the training effect result only from perseveration with the currently active set or from long-term learning? Experiment 1 supported the latter alternative: When training and test were separated by up to 1 week, to prevent perseveration across the 2 sessions, the training effect was still obtained. Second, is the learning feature-specific (tuned to a precise set of colors) or more abstract? Experiments 2 and 3 supported the latter: When stimulus colors were switched between training and test to remove the possibility of feature-specific learning, the training effect again was obtained. These experiments indicate that attentional set is largely guided by long-term abstract learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stimulus-driven attentional capture by a static discontinuity between perceptual groups.

After C. L. Folk, R. W. Remington, and J. C. Johnston (1992) proposed their contingent-orienting hypothesis, there has been an ongoing debate over whether purely stimulus-driven attentional capture can occur for visual events that are salient by virtue of a distinctive static property (as opposed to a dynamic property such as abrupt onset). The present study identified 3 methodological criteria for establishing that attentional capture is stimulus driven and not contingent on top-down attentional control settings. In 5 experiments, attentional capture occurred for a static discontinuity at the boundary between one group of homogeneous items (red Xs) abutted next to a group of homogeneous items that were featurally different (green Xs) within a single row. Experiment 1 intentionally violated one of the criteria for demonstrating stimulus-driven capture so as to establish that contingent attentional capture can occur for this novel type of static cue. In the remaining 4 experiments, even with all 3 criteria for stimulus-driven capture partially or completely satisfied, the static discontinuity captured attention. These attentional capture effects are the first to be obtained when all 3 criteria for establishing that they are purely stimulus driven have been satisfied. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional and perceptual factors affecting the attentional blink for faces and objects.

When 2 different visual targets presented among different distracters in a rapid serial visual presentation (RSVP) are separated by 400 ms or less, detection and identification of the 2nd targets are reduced relative to longer time intervals. This phenomenon, termed the attentional blink (AB), is attributed to the temporary engagement of a limited-capacity attentional system by the 1st target, which reduces resources available for processing the 2nd target. Although AB has been reliably obtained with many stimulus types, it has not been found for faces (E. Awh et al., 2004). In the present study, the authors investigate the underpinnings of this immunity. Unveiling circumstances in which AB occurs within and across faces and other categories, the authors demonstrate that a multichannel model cannot account for the absence of AB effects on faces. The authors suggest instead that perceptual salience of the face within the distracters' series as well as the available resources determine whether or not faces are blinked in RSVP. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Avoidance learning of perceptual defense and vigilance.

Thirty-two undergraduates were randomly assigned to defense and vigilance training groups. "This study supports the view that perceptual defense and vigilance are learned reactions to anxiety arousing stimuli." A behavior theory analysis of the learning process is proposed. "According to this analysis, perceptual defense is learned when the perceptual response to a threatening stimulus is punished and competing perceptual responses are instrumental to anxiety reduction. Competing perceptual responses when reinforced are strengthened at the expense of the critical perceptual response. Perceptual vigilance is learned when the perceptual response to a threatening stimulus is reinforced by anxiety reduction and competing perceptual responses are punished." Learning for both groups "proceeded in the absence of awareness." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hemispheric and attentional contributions to perceptual organization deficits on the global-local task in schizophrenia.

Right and left hemisphere hypotheses have been proposed to account for cognitive deficits in schizophrenia. To examine these hypotheses, perception of global-local patterns was studied in 22 patients with schizophrenia and 28 normal comparison participants. The patients with schizophrenia showed an abnormally exaggerated global processing advantage when attention was divided between global and local levels but not when participants were instructed to attend to either the local or global level. This finding suggested a local processing (left hemisphere) deficit, which was overcome through strategic attentional allocation (instructional set). When the stimulus visual angle was reduced from 9° to 3°, the normal participants showed a shift from a local to a global processing advantage, but the patients did not. This finding suggested a more subtle deficit in strategic attentional processes that develop through exposure to stimulus context. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inhibitory associations contribute to perceptual learning in humans.

Perceptual learning in humans was examined in 2 experiments. In Experiment 1, participants received intermixed exposure to 2 similar compounds (AX, BX, AX, BX, . . .) and blocked exposure to a 2nd pair of similar compounds (CY, CY, . . . , DY, DY, . . .). Aversions established to AX and CY generalized less to BX than to DY. In Experiment 2, 1 pair of compounds was presented in a forward order (i.e., AX3BX), whereas the 2nd pair of compounds was presented in a backward order (i.e., DY→CY). Aversions established to AX and CY generalized less to BX than to DY. These results indicate that inhibitory associations contribute to perceptual learning in humans and thereby establish a fundamental similarity between the mechanisms that underlie perceptual learning in humans and rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intersensory experience and early perceptual development: Postnatal experience with multimodal maternal cues affects intersensory responsiveness in Bobwhite Quail Chicks.

Unlike the other sensory modalities of precocial infants, the visual modality does not normally become functional until after birth or hatching. Despite this unique developmental status, the role of emerging visual experience on postnatal perceptual organization remains unclear. In this study, bobwhite quail hatchlings were reared in conditions that manipulated postnatal experience with maternal visual cues, either alone or in conjunction with maternal auditory cues. Results revealed that bobwhite chicks require postnatal exposure to both maternal auditory and visual cues following hatching to demonstrate species-specific perceptual preferences. Chicks that received temporally disparate maternal auditory and visual cues or experience with only maternal visual or maternal auditory cues failed to show species-typical perceptual responsiveness. These results suggest that developmental mechanisms involving both visual and auditory sensory experience underlie the emergence of early intersensory integration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Generalization of perceptual learning of vocoded speech.

Recent work demonstrates that learning to understand noise-vocoded (NV) speech alters sublexical perceptual processes but is enhanced by the simultaneous provision of higher-level, phonological, but not lexical content (Hervais-Adelman, Davis, Johnsrude, & Carlyon, 2008), consistent with top-down learning (Davis, Johnsrude, Hervais-Adelman, Taylor, & McGettigan, 2005; Hervais-Adelman et al., 2008). Here, we investigate whether training listeners with specific types of NV speech improves intelligibility of vocoded speech with different acoustic characteristics. Transfer of perceptual learning would provide evidence for abstraction from variable properties of the speech input. In Experiment 1, we demonstrate that learning of NV speech in one frequency region generalizes to an untrained frequency region. In Experiment 2, we assessed generalization among three carrier signals used to create NV speech: noise bands, pulse trains, and sine waves. Stimuli created using these three carriers possess the same slow, time-varying amplitude information and are equated for na?ve intelligibility but differ in their temporal fine structure. Perceptual learning generalized partially, but not completely, among different carrier signals. These results delimit the functional and neural locus of perceptual learning of vocoded speech. Generalization across frequency regions suggests that learning occurs at a stage of processing at which some abstraction from the physical signal has occurred, while incomplete transfer across carriers indicates that learning occurs at a stage of processing that is sensitive to acoustic features critical for speech perception (e.g., noise, periodicity). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Verbal redundancy in multimedia learning: When reading helps listening.

Three studies investigated whether and under what conditions the addition of on-screen text would facilitate the learning of a narrated scientific multimedia explanation. Students were presented with an explanation about the process of lightning formation in the auditory alone (nonredundant) or auditory and visual (redundant) modalities. In Experiment 1, the effects of preceding the nonredundant or redundant explanation with a corresponding animation were examined. In Experiment 2, the effects of presenting the nonredundant or redundant explanation with a simultaneous or a preceding animation were compared. In Experiment 3, environmental sounds were added to the nonredundant or redundant explanation. Learning was measured by retention, transfer, and matching tests. Students better comprehended the explanation when the words were presented auditorily and visually rather than auditorily only, provided there was no other concurrent visual material. The overall pattern of results can be explained by a dual-processing model of working memory, which has implications for the design of multimedia instruction. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does auditory streaming require attention? Evidence from attentional selectivity in short-term memory.

R. P. Carlyon, R. Cusack, J. M. Foxton, and I. H. Robertson (2001; see record 2001-16068-008) have argued that attention is crucial for auditory streaming. The authors review R. P. Carlyon et al.'s (2001) arguments and suggest that a pertinent literature, the irrelevant sound paradigm--demonstrating preattentive auditory streaming--has been overlooked. In illustration of this alternative approach, the authors include a novel single experiment demonstrating the impact of preattentive auditory streaming on short-term serial memory. It is concluded that R. P. Carlyon et al.'s (2001) results do not definitively demonstrate that auditory streaming processes are dependent on attention; indeed, they are compatible with alternative accounts of the relationship between perceptual organization and attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Constraints on learning new mappings between perceptual dimensions.

The constraints on learning new mappings between visual and proprioceptive spatial dimensions were assessed. Incomplete information was provided about a mapping by specifying only a few isolated visual–proprioceptive pairs of locations. The nature of the generalization occurring to untrained locations was then inspected to reveal the internal constraints. A new technique was developed to allow individual visual–proprioceptive pairs to be manipulated separately. In Experiment 1, training with only a single pair produced a rigid shift of one entire dimension with respect to the other. Training with two pairs caused linear interpolation to all untrained positions between the trained positions (Experiments 2 and 3). Finally, training with three new pairs also produced a linear change in behavior (Experiment 4), even though more adaptive solutions existed. The implications of these results for the learning process involved in acquiring new mappings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuroanatomical and cognitive mediators of age-related differences in perceptual priming and learning.

Our objectives were to assess age differences in perceptual repetition priming and perceptual skill learning and to determine whether they are mediated by cognitive resources and regional cerebral volume differences. Fragmented picture identification paradigm allows the study of both priming and learning within the same task. The authors presented this task to 169 adults (ages 18–80), assessed working memory and fluid intelligence, and measured brain volumes of regions that were deemed relevant to those cognitive skills. The data were analyzed within a hierarchical path modeling framework. In addition to finding age-related decrease in both perceptual priming and learning, the authors observed several dissociations with regards to their neural and cognitive mediators. Larger visual cortex volume was associated with greater repetition priming, but not perceptual skill learning, and neither process depended upon hippocampal volume. In contrast, the volumes of the prefrontal gray and white matter were differentially related to both processes via direct and indirect effects of cognitive resources. The results indicate that age-related differences in perceptual priming and skill learning have dissociable cognitive and neural correlates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)