Attentional processing and the independence of color and orientation.

Judgments of the color and shape of a stimulus specified by a cue indicating its location demonstrate stochastic independence. Evidence for the independence of color and orientation was obtained when the cue followed stimulus offset immediately, the cue followed stimulus offset by 2 sec, and when either a central or peripheral precue focused attention on the cued stimulus at the time of its presentation. It appears that an object's color and orientation are represented independently even following the attentional focusing thought to support feature integration. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention and luminance detection: A quantitative analysis.

Two experiments investigated the effects of spatial cues on the detection of luminance targets in global (nonlocalizing) and local (poststimulus probe) detection tasks. Cuing effects were quantified by fitting a variety of single- and multiple-channel signal-detection models to the data from individual observers. The local detection data showed enhanced sensitivity at cued locations, consistent with previous findings. Models for global detection in which cues affected both sensitivity and criterion or criterion alone could not be distinguished reliably on the basis of goodness-of-fit statistics. However, estimated model parameters showed that under global detection conditions, sensitivity was enhanced at cued locations by a factor of around 2. Results are discussed relative to a model in which Poisson-coded sensory representations are modulated by spatial attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention to overlapping objects: Detection and discrimination of luminance changes.

Selective attention to 1 of 2 overlapping objects was assessed in a cuing paradigm. Participants detected or identified targets that appeared in 1 of 6 possible target locations (3 on each object). Significant cuing effects for the simple detection of such targets using both reaction time and sensitivity measures of performance were found. Cuing effects were consistently greater when the participants were required to identify some aspect of the target even when the tasks (detection vs. identification) were equated for overall performance level. These differences in cuing effects between tasks were much reduced if the target locations were no longer grouped into 2 objects. It is suggested that identical stimuli can elicit differing attentional mechanisms depending on task type (rather than task difficulty) and that these mechanisms differ in the nature of the representation of the visual world. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention and luminance detection: Effects of cues, masks, and pedestals.

Three experiments investigated the effects of attention on the detection of luminance targets in a spatial-cuing paradigm. Gabor patch stimuli of 30, 60, or 90 ms duration, equated for detectability, were presented (a) against a uniform field with a checkerboard backward mask, (b) atop a 15% luminance pedestal with a backward mask, or (c) atop a luminance pedestal with no backward mask. Signal detection analysis showed that detection sensitivity was significantly enhanced at attended locations for all observers when backward masks were used, both when targets were presented against a uniform field and when a pedestal was used. However, when no masks were used there was no cuing advantage of any kind. The results show that the cuing effect in simple detection depends on the use of backward masks, a finding that resolves the inconsistencies previously associated with studies of this type. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mood-Congruent Attentional Bias in Dysphoria: Maintained Attention to and Impaired Disengagement From Negative Information.

Attentional bias to negative information has been proposed to be a cognitive vulnerability factor for the development of depression. In 2 experiments, the authors examined mood-congruent attentional bias in dysphoria. In both experiments, dysphoric and nondysphoric participants performed an attentional task with negative, positive, and neutral word cues preceding a target. Targets appeared either at the same or at the opposite location of the cue. Overall, results indicate that dysphoric participants show maintained attention for negative words at longer stimulus presentations, which is probably caused by impaired attentional disengagement from negative words. Furthermore, nondysphoric participants maintain their attention more strongly to positive words. These results are discussed in relation to recent developments in the pathogenesis and treatment of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Covariation of color and luminance facilitate object individuation in infancy.

The ability to individuate objects is one of our most fundamental cognitive capacities. Recent research has revealed that when objects vary in color or luminance alone, infants fail to individuate those objects until 11.5 months. However, color and luminance frequently covary in the natural environment, thus providing a more salient and reliable indicator of distinct objects. For this reason, we propose that infants may be more likely to individuate when objects vary in both color and luminance. Using the narrow-screen task of Wilcox and Baillargeon (1998a), in Experiment 1 we assessed 7.5-month-old infants' ability to individuate uniformly colored objects that varied in both color and luminance or luminance alone. Experiment 2 further explored the link between color and luminance by assessing infants' ability to use pattern differences that included luminance or color to individuate objects. Results indicated that infants individuated objects only when covariations in color and luminance were used. These studies add to a growing body of literature investigating the interaction of color and luminance in object processing in infants and have implications for developmental changes in the nature and content of infants' object representations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Early Social Attention Impairments in Autism: Social Orienting, Joint Attention, and Attention to Distress.

This study investigated social attention impairments in autism (social orienting, joint attention, and attention to another's distress) and their relations to language ability. Three- to four-year-old children with autism spectrum disorder (ASD; n = 72), 3- to 4-year-old developmentally delayed children (n = 34), and 12- to 46-month-old typically developing children (n = 39), matched on mental age, were compared on measures of social orienting, joint attention, and attention to another's distress. Children with autism performed significantly worse than the comparison groups in all of these domains. Combined impairments in joint attention and social orienting were found to best distinguish young children with ASD from those without ASD. Structural equation modeling indicated that joint attention was the best predictor of concurrent language ability. Social orienting and attention to distress were indirectly related to language through their relations with joint attention. These results help to clarify the nature of social attention impairments in autism, offer clues to developmental mechanisms, and suggest targets for early intervention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Self-complexity, self-evaluation, and depression: An examination of form and content within the self-schema.

Six studies examined the relationship between self-complexity and variables related to self-evaluation. Self-complexity was found to comprise two components: positive self-complexity and negative self-complexity. Positive self-complexity was sensitive to methodological factors, namely, variations in stimulus materials used for self-ratings. Negative self-complexity was relatively stable in the face of different rating stimuli and tasks and was related to trait measures of self-evaluation, psychic distress, and psychopathology. These findings were observed and replicated. Higher negative self-complexity was associated with increases in depression symptoms over time. Higher negative self-complexity also predicted a poorer prognosis and less complete recovery from depression in a clinical sample. Results are discussed in light of related research and possible social–cognitive mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conjunction of color and form without attention: Evidence from an orientation-contingent color aftereffect.

According to A. Treisman and G. Gelade's (see record 1980-04685-001) feature-integration theory, separable features such as color and shape exist in separate maps in preattentive vision and can be integrated only through the use of spatial attention. However, many perceptual aftereffects, which are also assumed to reflect the features available in preattentive vision, are sensitive to conjunctions of features. One possible resolution of these views holds that adaptation to conjunctions depends on spatial attention. Exp I tested this proposition by presenting 24 undergraduates with gratings varying in color and orientation. The resulting McCollough aftereffects were independent of whether the adaptation stimuli were presented inside or outside of the focus of spatial attention. Therefore, color and shape appear to be conjoined preattentively when perceptual aftereffects are used as the measure. These same stimuli, however, appeared to be separable in Exps II and III, which required 24 Ss to search for gratings of a specified color and orientation. These results show that different experimental procedures may be tapping into different stages of preattentive vision. (63 ref) (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Similar electrophysiological correlates of texture segregation induced by luminance, orientation, motion and stereo

Certain local features induce preattentive texture segregation. Recently, components in the visual evoked potential (VEP) associated with preattentive texture segregation (tsVEPs) have been demonstrated. To assess the similarity and dissimilarity of visual processing across visual dimensions, we compared VEPs and tsVEPs in texture segregation by luminance, orientation, motion and stereo disparity. We found tsVEPs across these four visual dimensions to be remarkably similar when compared to the "low-level" VEPs. The tsVEPs were always negative; their implicit time, peak latency and amplitude were (in msec/msec/microV): 91/234/-5.7, luminance; 84/257/-3.9, orientation; 80/295/-8.3, motion; and 95/310/-5.0 for stereo. The cross-correlation function, as a quantitative measure for similarity, on average was higher for the tsVEPs by a factor of 4.2 as compared to the low-level VEPs (P < 0.0001). The results suggest (1) that the tsVEPs represent activity of neural mechanisms that have generalised to some degree across visual dimensions; and (2) that these hypothetical generalisation mechanisms might exist already in the primary visual cortex.     

Selection by color and form in vision.

Whether attention to a local part of a visual display can prevent access to semantic information in form matching tasks with objects was studied. A first picture containing a line segment (the reference) was followed by 2 lateral objects also containing a line segment (a target and a distractor). Participants matched the line segments according to either their orientation or color. Effects of semantic information were assessed by manipulating the semantic relations among the pictures surrounding the reference, target, and distractor. Semantic information affected performance in the orientation matching task, but not in the color matching task. Results suggest the existence of separate selection mechanisms in vision. Selection of local colors for response purposes can be based on inhibition of the form pathway (eliminating semantic effects on matching). Selection within the form pathway can involve a bias toward global shape (the picture). Once attention is allocated to global shape, associated semantic representations are activated and semantic effects on matching emerge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neural dynamics of form perception: Boundary completion, illusory figures, and neon color spreading.

Describes the use of a real-time visual processing theory to analyze real and illusory contour formation, contour and brightness interactions, neon color spreading, complementary color induction, and filling-in of discounted illuminants and scotomas. The theory also physically interprets and generalizes E. H. Land's (see record 1979-05257-001) retinex theory. These phenomena are traced to adaptive processes that overcome limitations of visual uptake to synthesize informative visual representations of the external world. Two parallel contour-sensitive processes interact to generate the theory's brightness, color, and form estimates. A boundary contour process is sensitive to orientation and amount of contrast but not to direction of contrast in scenic edges. It synthesizes boundaries sensitive to the global configuration of scenic elements. A feature contour process is insensitive to orientation but sensitive to both amount of contrast and to direction of contrast in scenic edges. It triggers a diffusive filling-in of featural quality within perceptual domains whose boundaries are determined by completed boundary contours. The boundary contour process is hypothesized to include cortical interactions initiated by hypercolumns in Area 17 of the visual cortex. The feature contour process is hypothesized to include cortical interactions initiated by the cytochrome oxydase staining blobs in Area 17. Data from striate and prestriate visual cortex experiments are reviewed, and predictions based on these data are tested. (92 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Featural guidance in conjunction search: The contrast between orientation and color.

Four experiments examined the effects of precues on visual search for targets defined by a color-orientation conjunction. Experiment 1 showed that cueing the identity of targets enhanced the efficiency of search. Cueing effects were stronger with color than with orientation cues, but this advantage was additive across array size. Experiment 2 demonstrated that cueing effects interacted with bottom-up segmentation processes, whereas Experiment 3 showed the stronger effects of color cues remained in a compound task. Experiment 4 confirmed the enhanced effect of color cueing even when verbal rather than visual cues were used. The targets used were balanced for search efficiency within both orientation and color dimensions. We suggest search benefits from the top-down cueing of color compared with orientation because color cueing enhances the segmentation of displays into color groups more efficiently. This enables search to an appropriate color group to be initiated earlier. We discuss how top-down segmentation processes interact with differences in bottom-up segmentation to further improve target detection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention within auditory word perception: Insights from the phonemic restoration illusion.

Conducted 2 experiments to determine the extent to which attention plays a role in the phonemic restoration illusion and to infer from this the nature of attention in auditory word perception. Exp I examined the effect of training on the magnitude of the phonemic restoration illusion. 24 Ss received training with the potentially restorable stimuli (972 trials with feedback); in addition, the presence or absence of an attentional cue, contained in a visual prime preceeding each trial, was varied between groups of Ss. Findings reveal that cuing the identity and location of the critical phoneme of each test word allowed Ss to attend to the critical phoneme, thereby inhibiting the illusion, but only when the prime also identified the test word itself. Exp II was a 2-part replication of Exp I, using 92 Ss and some modifications of the conditions. Results show that when the prime provided only the identity or location of the critical phoneme, or only the identity of the word, Ss performed identically to those Ss for whom the prime contained no information at all about the test word. Training did not produce any generalized learning about the types of stimuli used. Results indicate that attention is necessary to perceive phonemic units selectively and is focused through the level that has primacy in the perception of spoken words, the mental lexicon. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A cognitive approach to intelligence: Attention, coding and planning.

Reviews the progress of the planning-attention-simultaneous-successive (PASS) theory, described by J. P. Dass (1972, 1973). The theory describes behavior as the result of the interdependent functioning of planning, attention (arousal), and coding (either simultaneous or successive) systems. Most research conducted to 1979 concerned simultaneous and successive coding in working memory and relied on principle components analyses. Research since 1980 has examined the roles of arousal, especially in attention, and of the planning system; experimental studies and confirmatory analyses have also been conducted. Relationships of PASS theory to other theories and approaches are considered. Three areas of application are examined: understanding achievement skills and learning problems, theory-based assessment of cognitive processes, and instructional design. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Developmental changes within the structure of the mammal domain.

Examined and considered developmental changes in the organization of information within the mammal domain within the context of cultural knowledge acquisition. Judgments of similarity among mammals were elicited from 7-yr-olds, 10-yr-olds, and adults by means of a triad task. Analysis addressed both quantitative and qualitative models of development consistent with the A. K. Romney et al (1986) cultural consensus model. Results provided partial support for both models. Ss' responses generally fit the cultural consensus model, whereas systematic patterns of deviation from the model emerged between children and adults because of the emergence of a primate category after age 10. The relationship between these results and S. Carey's (1985) research on the development of biological knowledge is discussed, and implications for the study of expertise acquisition are considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attentional bias to threat: A perceptual accuracy approach.

To investigate attentional bias to threatening information, the authors propose a new version of the spatial cueing paradigm in which the focus is on perceptual accuracy instead of response speed. In two experiments, healthy volunteers made unspeeded discriminations between three visual targets presented left or right. Each target was preceded by a visual cue (colored rectangle) at either the same (valid) or opposite (invalid) location. By means of differential classical conditioning with aversive white noise, a threat cue and a control cue were created. Analyses of error rates showed that cueing effects (lower proportion of errors in valid trials relative to invalid trials) were more pronounced in threat trials than in neutral trials. This threat-related bias was particularly because of threat cues reducing accuracy in invalid trials, indicating difficulty disengaging attention from threatening information. Engagement of attention was not affected by threat, as threat cues did not facilitate the processing of targets in valid trials. The findings are discussed in light of the strengths and limitations of spatial cueing tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

How Does Attention Select and Track Spatially Extended Objects? New Effects of Attentional Concentration and Amplification.

Real-world situations involve attending to spatially extended objects, often under conditions of motion and high processing load. The present experiments investigated such processing by requiring observers to attentionally track a number of long, moving lines. Concurrently, observers responded to sporadic probes as a measure of the distribution of attention across the lines. The results revealed that attention is concentrated at the centers of lines during tracking, despite their uniformity, and that this center advantage grew as the lines became longer: Not only did observers get worse near the endpoints, but they became better at the lines' centers, as if attention became more concentrated as the objects became more extended. These results begin to show how attention is flexibly allocated in online visual processing to extended dynamic objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Unconscious perception: Attention, awareness, and control.

Conscious perception is substantially overestimated when standard measurement techniques are used. That overestimation has contributed to the controversial nature of studies of unconscious perception. A process-dissociation procedure (L. L. Jacoby; see record 1992-07943-001) was used for separately estimating the contribution of conscious and unconscious perception to performance of a stem-completion task. Unambiguous evidence for unconscious perception was obtained in 4 experiments. In Exp 1, decreasing the duration of a briefly presented word diminished the contribution of both conscious and unconscious perception. In Exps 2–4, dividing attention reduced the contribution of conscious perception while leaving that of unconscious perception unchanged. Discussion focuses on the measurement of awareness and the relation between perception and memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)