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New research supports connectionist network models and classical learning theories indicating that learning boosts the strength of discriminate signals. It is still unclear how signal enhancement shows itself at the neuronal level. This research involved making sets of faces and textures whose signal strength could be changed. Observers were trained to identify these patterns embedded in noise. Performance improved by up to 400% across a number of sessions. Learning boosted the efficiency with which observers encoded task-relevant information. It appears that the neural correlates of behaviour should show improved discrimination among stimuli and constant variability during perceptual learning.

Studies done by researchers in Canada on the perceived instrumentality of unions suggests that family socialization plays a vital part in its development. This model puts forward two predictors of general union attitudes, the perceived attitudes of the parents towards unions and their perceived union activity participation. Influence based on perceived parent union participation on a person's general attitude towards a union is modified by the individual's perception of general union attitudes by the parents., The Fulcrum of the unionization process is widely considered to be the perceived instrumentality of unions (Barling, Fullagar, & Kelloway, 1992; DeCotiis & LeLouarn, 1981). Perceived union instrumentality is defined [...]

A clock paradigm was employed to assess whether temporal preparation decreases the time to detect the onset of a stimulus - that is, perceptual latency. In four experiments participants watched a revolving clock hand while listening to soft or loud target tones under high or low temporal preparation. At the end of each trial, participants reported the clock hand position at the onset of the target tone. The deviation of the reported clock hand position from the actual position indexed perceptual latency. As expected, perceptual latency decreased with target tone intensity. Most importantly, however, greater temporal preparation decreased perceptual latency in all four experiments, especially for soft tones, which supports rather directly the idea that temporal preparation diminishes the duration of perceptual processing.

Theoretical analyses of perceptual learning suggest that comparison between similar stimuli aids subsequent discrimination between them. The current studies examined whether the opportunity to compare a target face to other similar faces during a preexposure phase facilitated performance on a matching task. Performance was better when the target face had been presented in alternation with similar comparator faces than if that target had not been exposed before test. Exposure to the target face without comparators, or exposure alternating with dissimilar faces, improved performance relative to the nonexposed control but performance was not as good as when target exposure was given in alternation to similar comparison faces. The effects were not influenced by image changes between exposure and test. It is suggested that exposure to a face in comparison to similar stimuli focuses the central representation of a face on its unique features. In practical terms these results suggest that reliable identification of an individual from their photograph would be improved by viewing that photograph in comparison with photographs of similar people.

Human participants received unsupervised exposure to difficult-to-discriminate chequerboard stimuli (e.g., AX and BX), before learning a discrimination between them. Experiment 1 demonstrated that prior exposure enhanced later discrimination and that intermixed exposure (AX, BX, AX, BX ...) resulted in better subsequent discrimination than did blocked exposure (CY, CY ... DY, DY ...). Experiment 2 showed that simultaneous exposure to two similar stimuli (AX-BX, BX-AX ...) facilitated the later acquisition of a successive discrimination, more than successive exposure (AX-AX, BX-BX ...). These results parallel those observed by Mundy, Honey, and Dwyer (2007) who used pictures of human faces as stimuli and establish the generality of the fact that simultaneous exposure produces a particularly marked perceptual learning effect.

A study is conducted to know how perceptual systems dynamically adjust to reflect the speech one hear and what causes the representations to return to the pre-perceptual learning setting. The results revealed that phonemic representations are dynamic and flexible to interact with both higher (lexical) and lower-level (acoustic) information.

A study is conducted to thoroughly test the implicit associative response (IAR)/ imagery account of perceptual critical item priming. The study concluded that false memories do not inherently contain structural and perceptual information and past reports of critical item priming relied on implicit tests more prone to conceptual activation.

A hallmark of perceptual expertise is that experts classify objects at a more specific, subordinate level of abstraction than novices. To what extent does subordinate-level learning contribute to the transfer of perceptual expertise to novel exemplars and novel categories? In this study, participants learned to classify 10 varieties of wading birds and 10 varieties of owls at either the subordinate, species (e.g., 'great blue crown heron,''eastern screech owl') or the family ('wading bird,''owl') level of abstraction. During training, the amount of visual exposure was equated such that participants received an equal number of learning trials for wading birds and owls. Pre- and posttraining performance was measured in a same/different discrimination task in which participants judged whether pairs of bird stimuli belonged to the same or different species. Participants trained in species-level discrimination demonstrated greater transfer to novel exemplars and novel species categories than participants trained in family-level discrimination. These findings suggest that perceptual categorization, not perceptual exposure per se, is important for the development and generalization of visual expertise.

Teachers gesture when they teach, and those gestures do not always convey the same information as their speech. Gesture thus offers learners a second message. To determine whether learners take advantage of this offer, we gave 160 children in the third and fourth grades instruction in mathematical equivalence. Children were taught either one or two problem-solving strategies in speech accompanied by no gesture, gesture conveying the same strategy, or gesture conveying a different strategy. The children were likely to profit from instruction with gesture, but only when it conveyed a different strategy than speech did. Moreover, two strategies were effective in promoting learning only when the second strategy was taught in gesture, not speech. Gesture thus has an active hand in learning.

Rats received different schedules of pre-exposure to a compound flavor (AX) and to one element of that compound (X). Establishing an aversion to X and measuring the generalization of this aversion to AX assessed discrimination between AX and X.

The attributional process that mediates the role of perceptual fluency in recognition memory is addressed in three experiments that study the initial processing of a stimulus. The findings confirm the relevance of perceptual fluency as a sign of prior occurrence moderating its effect on recognition memory judgments.

The nonhumans capability to form conceptual versus perceptual discriminations is discussed. In this connection, a young gorilla was trained at three levels of abstraction that is concrete, intermediate and abstract, which showed that the gorilla was able to discriminate positive from the negative exemplars.

We investigated the influence of mood states on the framing effect on tasks that involve systematic processing and on a task that involves heuristic processing. On the systematic processing tasks, the framing effect was not exhibited under induced mood states, while on the heuristic processing task, the framing effect was exhibited under induced mood states. The relationship between mood states and the framing effect was discussed from the standpoint of an information-processing mechanism.

Although traditionally texture segmentation has been regarded as an automatic, preattentive process, participants confronted with texture segmentation in experimental settings (i.e., with brief presentation time and subsequent masking) are initially unable to perform the task. According to perceptual learning concepts, participants must learn to fine-tune their sensory channels before perception improves under restricted viewing conditions. The present article proposes an alternative perspective that emphasizes the role of the mask. Four experiments showed that the amount of observed learning depends on the structural and temporal homogeneity or heterogeneity of the mask. The authors suggest that learning consists of separating the task-relevant signal stemming from the texture from the task-irrelevant signal of the mask and of ignoring the mask.

The distinction made by Page between localist and distributed representations seems confounded by the distinction between competitive and associative learning. His manifesto can also be read as a plea for competitive learning. The power of competitive models can even be extended further, by simulating similarity effects in forced-choice perceptual identification (Ratcliff & McKoon 1997) that have defied explanation by most memory models.

Perceptual organization offers an elegant framework to group low-level features that are likely to come from a single object. We offer a novel strategy to adapt this grouping process to objects in a domain. Given a set of training images of objects in context, the associated learning process decides on the relative importance of the basic salient relationships such as proximity, parallelness, continuity, junctions, and common region toward segregating the objects from the background. The parameters of the grouping process are cast as probabilistic specifications of Bayesian networks that need to be learned. This learning is accomplished using a team of stochastic automata in an N-player cooperative game framework. The grouping process, which is based on graph partitioning is, able to form large groups from relationships defined over a small set of primitives and is fast. We statistically demonstrate the robust performance of the grouping and the learning frameworks on a variety of real images. Among the interesting conclusions are the significant role of photometric attributes in grouping and the ability to form large salient groups from a set of local relations, each defined over a small number of primitives. Index Terms--Perceptual organization, learning in vision, learning automata, Bayesian networks, feature grouping, object recognition, figure ground segmentation.

Both semantic priming and perceptual priming consist of facilitation of the identification of primed stimuli and inhibition of the identification of nonprimed stimuli. The similarities betwee the two phenomena suggest that a common attentional mechanism underlies both, and this has been explicitly proposed by several attention theorists. In this article it is argued that the phenomena of semantic and perceptual priming are qualitatively different, perceptual priming reflecting a sensitivity change in the recognition process brought about by attention, and semantic priming reflecting a bias change in the recognition process brought about by attention. Because different mechanisms are required to produce sensitivity and bias changes, this implies that the attentional mechanisms responsible for semantic and perceptual priming are distinct. In terms of recent discussions of the modularity versus the unity of cognitive architecture, the present conclusion support a modular architecture for attentional processes.

Perceptual learning was examined in two experiments in which subjects, originally unfamiliar with vibrotactile stimulation, were required to identify dynamic vibrotactile patterns with static visual patterns of the same two-dimensional shapes. In Experiment 1 we examined changes in performance with practice under a variety of vibrotactile spatial and temporal conditions. In Experiment 2 we investigated transfer of learning from one set of vibrotactile patterns to another different set. In neither experiment were subjects supplied with knowledge of results. Substantial perceptual learning (improvement in identification with practice) was observed in Experiment 1, although a minority of subjects did not exhibit improvement. Experiment 2 confirmed the general findings of Experiment 1 and also provided evidence of substantial positive transfer. In both experiments, multidimensional scaling of pattern confusion data revealed that practice (and improvement in identification) did not qualitatively change the relative confusability of patterns, suggesting that the (informative) structure of the patterns, irrespective of familiarity with a specific set of patterns, determined confusability. The findings are interpreted in terms of learning constructs offered by E. J. and J. J. Gibson. We conclude by considering the prospects that a connectionist mechanism can account for the observed perceptual learning.

Lewicki, Czyzewska,and Hoffman (1987) demonstrated learning without awareness in a visual search task. Rules determined target location on every seventh trial on the basis of target locations in the preceding six trials. Learning was demonstrated by negative transfer effects when the rules were changed. When questioned afterwards, the subjects could not describe the rules and denied awareness of them. This experimetn was designed to replicate that of Lewicki et al. and to test several hypotheses about this apparent learning without awareness. Transfer conditions were included to determine whether rule learning was primarily perceptual or motor. The present assessment of awareness was based on an objective definition of awareness, rather than a subjective definition as in Lewicki et al.'s study. Their effect was replicated, and the transfer conditions revealed that learning relied on perceptual aspects of the task. The objective measure of awareness provided further evidence that subjects were unaware of the rules.

The mere repetition of events tends to enhance subjective familiarity and subjective preference for those events. It has been shown that the enhancement of subjective preference is neither contingent upon a feeling of familiarity nor an awareness of the physical identity of the stimulus during learning. This finding is surprising since the weight of existing theoretical and empirical evidence suggests that subjective preference is derivative of familiarity. An experiment was conducted to test the hypothesis that at least one preattentive/preconscious product, figure-ground organization, is shared between the processes responsible for preference enhancement and those responsible for the enhancement of recognition memory. There were two significant findings. First, subjects were able to discriminate between objectively familiar stimuli and objectively unfamiliar stimuli on the basis of preference judgments but were unable to do so on the basis of familiarity judgments. Second, preference enhancement occurred only for those objectively familiar stimuli for which the figure-ground aspects had not been phenomenally reversed. The significance of these findings is discussed.

The Trail Making Test for children was administered to 268 subjects between the ages of 10 and 15 yr. All subjects reported normal psychological histories. When responses were compared with those reported by Reitan in 1971 differences were noted between the two samples. The possibility that the test may not be free of cultural influences is contemplated. The results suggest the use of local normative data in interpreting the scores obtained on this test.