Does attention follow the motion in the “shooting line” illusion?

When a line is presented in the vicinity of a recent luminance change (peripheral cue), it is perceived to be drawn over time away from its “cued” end even though the line is actually presented all at once. This study was designed to determine whether attention, exogenously attracted to the cue, would come under the exogenous control of this illusory motion and follow the drawing motion from the cued end to its terminus. Each trial began with the display of four small squares at the corners of an imaginary square centered about fixation. On the critical trials, one of the four squares brightened briefly, after which a horizontal line was presented joining either the two upper or the two lower squares. Shortly thereafter, the distribution of attention was determined by asking the observer to indicate the nature of a change that was equally likely to occur to one of the squares. Responses to targets presented at a noncued location that was at the end of an illusorily drawn line were as fast as those to targets at the cued location and were much faster than those to targets at the remaining noncued locations. This pattern was not shown when the line preceded the cue, strongly suggesting that attention follows the motion in this illusion.     

Does attention follow the motion in the "shooting line" illusion?

When a line is presented in the vicinity of a recent luminance change (peripheral cue), it is perceived to be drawn over time away from its "cued" end even though the line is actually presented all at once. This study was designed to determine whether attention, exogenously attracted to the cue, would come under the exogenous control of this illusory motion and follow the drawing motion from the cued end to its terminus. Each trial began with the display of four small squares at the corners of an imaginary square centered about fixation. On the critical trials, one of the four squares brightened briefly, after which a horizontal line was presented joining either the two upper or the two lower squares. Shortly thereafter, the distribution of attention was determined by asking the observer to indicate the nature of a change that was equally likely to occur to one of the squares. Responses to targets presented at a noncued location that was at the end of an illusorily drawn line were as fast as those to targets at the cued location and were much faster than those to targets at the remaining noncued locations. This pattern was not shown when the line preceded the cue, strongly suggesting that attention follows the motion in this illusion.     

Does visual experience influence the spatial distribution of auditory attention?

Sighted individuals are less accurate and slower to localize sounds coming from the peripheral space than sounds coming from the frontal space. This specific bias in favour of the frontal auditory space seems reduced in early blind individuals, who are particularly better than sighted individuals at localizing sounds coming from the peripheral space. Currently, it is not clear to what extent this bias in the auditory space is a general phenomenon or if it applies only to spatial processing (i.e. sound localization). In our approach we compared the performance of early blind participants with that of sighted subjects during a frequency discrimination task with sounds originating either from frontal or peripheral locations. Results showed that early blind participants discriminated faster than sighted subjects both peripheral and frontal sounds. In addition, sighted subjects were faster at discriminating frontal sounds than peripheral ones, whereas early blind participants showed equal discrimination speed for frontal and peripheral sounds. We conclude that the spatial bias observed in sighted subjects reflects an unbalance in the spatial distribution of auditory attention resources that is induced by visual experience.     

Does the isolation effect require attention?

An item that differs from the surrounding items is remembered better than an item that is consistent with its surroundings; this is known as the von Restorff effect or isolation effect (von Restorff, Psychologische Forschung, 18, 299–342, 1933). Theoretical explanations have proposed that the isolate is processed differently from control items, though some research has suggested that this processing might require more attention for semantic than for physical isolates. To test this possibility, in the present study we examined the isolation effects for physical isolates and semantic isolates under full and divided attention. Participants viewed lists of categorized words, with some lists containing either a physical or a semantic isolate, followed by immediate written free recall. Across three experiments, divided attention eliminated the semantic isolation effect but did not impact the physical isolation effect. Furthermore, semantic isolates were output earlier in recall than controls, whereas physical isolates were output more similarly to controls. These findings suggest that semantic isolation effects require attention during encoding, whereas physical isolation effects are relatively automatic.     

Does contingency awareness mediate the influence of emotional learning on the cueing of visual attention?

Previous research has indicated that conditioning depends on contingency awareness (CA). However, we argue that these studies have examined this issue under methodological conditions that might be insensitive to associative learning without CA. In the present study we examined the effect of an experimental manipulation of CA on attentive processing of classically conditioned stimuli, which is sensitive to associative learning with and without CA. We found that aversive conditioning with additional contingency instructions modulated visual attention, in the sense that the conditioned cues captured and held attention more strongly than the non-conditioned cues. Surprisingly, conditioning under conditions of restricted CA yielded a response pattern that was different from that under full CA. These findings suggest that conditioning with full and restricted CA can lead to qualitatively different effects on attention.     

Does the corollary discharge of attention exist?

We discuss experimental support for the existence of a corollary discharge signal of attention movement control and its formulation in terms of the corollary discharge of attention model of attention movement (CODAM). The data is from fMRI, MEG and EEG activity observed about 200 ms after stimulus onset in various attention paradigms and in which the activity is mainly sited in parietal and extra-striate visual areas. Moreover the data arises from neural activity observed before report of a subject's experience occurs. The overall experimental support for the existence of a copy of the attention movement control signal generates, it is suggested, a viable route to explore the relation between this signal and human consciousness, as concluded in the paper.     

The octave illusion revisited: suppression or fusion between ears?

The octave illusion occurs when each ear receives a sequence of tones alternating by 1 octave but with the high and low tones in different ears. Most listeners perceive these stimuli as a high pitch in one ear alternating with a low pitch in the other ear. D. Deutsch and P. L. Roll (1976) interpreted this phenomenon as evidence for a what-where division of auditory processing caused by sequential interactions between the tones. They argued that the pitch follows the frequency presented to the dominant ear but is lateralized toward the higher frequency component. This model was examined in 4 experiments. Results indicate that the perceived pitch approximates the fundamental frequency and that the illusion does not depend on sequential interactions. The octave illusion may arise from an interaction between dichotic fusion and binaural diplacusis rather than from suppression as proposed by Deutsch.     

Does contextual cuing guide the deployment of attention?

Contextual cuing experiments show that when displays are repeated, reaction times to find a target decrease over time even when observers are not aware of the repetition. It has been thought that the context of the display guides attention to the target. The authors tested this hypothesis by comparing the effects of guidance in a standard search task with the effects of contextual cuing. First, in standard search, an improvement in guidance causes search slopes (derived from Reaction Time x Set Size functions) to decrease. In contrast, the authors found that search slopes in contextual cuing did not become more efficient over time (Experiment 1). Second, when guidance was optimal (e.g., in easy feature search), they still found a small but reliable contextual cuing effect (Experiments 2a and 2b), suggesting that other factors, such as response selection, contribute to the effect. Experiment 3 supported this hypothesis by showing that the contextual cuing effect disappeared when the authors added interference to the response selection process. Overall, the data suggest that the relationship between guidance and contextual cuing is weak and that response selection can account for part of the effect.     

Does attention alter appearance?

Abrupt onsets in the visual field can change the appearance of subsequent stimuli, according to one interpretation, by engaging an attentional mechanism that increases effective stimulus contrast. However, abrupt onsets can also engage capacity-unlimited and thus attention-independent sensory mechanisms. We conducted a series of experiments to differentiate the sensory and attentional accounts. Observers compared the contrasts of uncued low-contrast peripheral targets with simultaneous targets cued by one of three cue types with different sensory attributes: white or black peripheral abrupt onsets and central gaze direction cues devoid of sensory activity near the target locations. Each cue facilitated the perception of perithreshold targets; however, the white abrupt onsets increased the perceived contrast of suprathreshold targets, whereas the black abrupt onsets tended to reduce the perceived contrast, and the gaze direction cues had no significant effect. The effectiveness of the gaze direction cues in automatically orienting attention was demonstrated in a control experiment in which they consistently speeded response times. The results suggest that sensory interaction, and not attention, is responsible for changes in appearance.     

Does dividing attention become harder with age? findings from the divided attention questionnaire

Abstract

We developed a self-assessment scale, the Divided Attention Questionnaire (DAQ), to investigate whether adults report that dividing attention between two activities becomes more difficult with increasing age, as would be predicted by a model of age-related reductions in inhibition (Hasher & Zacks, 1988). the DAQ difficulty rating scale produced satisfactory estimates of internal consistency and test-retest stability. Older adults, relative to young adults, rated most combinations of activities as more difficult, and also reported that most combinations had become more difficult over time. However, self-perceptions of ability in old age varied with task domain, such that activities that involved monitoring of novel information became increasingly difficult with advanced age, while routine activities and those involving speech processing showed little change across the older groups studied. We suggest that belieft about self-efficacy under conditions of divided attention can have important consequences for the behavior of the elderly.     

Selective attention and asymmetry in the Müller-Lyer illusion

Two experiments reexamined the effect of selective spatial attention on the magnitudes of the wings- in and wings-out forms of the Müller-Lyer (M-L) illusion and a version of the illusion in which the two forms are superimposed to produce a figure (XX) flanked at both ends by an X. For the XX figure, ignoring the outer wings produced significant underestimation of shaft length, whereas ignoring the inner wings had no significant effect. For the M-L figures, ignoring the wings was more effective in attenuating the magnitude of the wings-out than of the wings-in illusion. The results are discussed with reference to space-based approaches to visual attention and to claims that attentional modulation of illusion magnitudes implicates high-level or cognitive factors in the formation of the M-L illusion.     

Modulations of the processing of line discontinuities under selective attention conditions?

We examined whether the processing of discontinuities involved in figure-ground segmentation, like line ends, can be modulated under selective attention conditions. Subjects decided whether a gap in collinear or parallel lines was located to the right or left. Two stimuli were displayed in immediate succession. When the gaps were on the same side, reaction times (RTs) for the second stimulus increased when collinear lines followed parallel lines, or the reverse, but only when the two stimuli shared the same orientation and location. The effect did not depend on the global form of the stimuli or on the relative orientation of the gaps. A frame drawn around collinear elements affected the results, suggesting a crucial role of the "amodal" orthogonal lines produced when line ends are aligned. Including several gaps in the first stimulus also eliminated RT variations. By contrast, RT variations remained stable across several experimental blocks and were significant for interstimulus intervals from 50 to 600 msec between the two stimuli. These results are interpreted in terms of a modulation of the processing of line ends or the production of amodal lines, arising when attention is selectively drawn to a gap.     

Is visual illusion decrement based on selective adaptation?

Illusion decrement is the reduction in the magnitude of visual geometric illusions with continued exposure, and it has been explained in two ways. The first explanation is the selective adaptation, or fatigue, of neural channels carrying orientation and/or spatial frequency information; the second explanation involves perceptual learning, in which the observer changes viewing strategy after continued exposure to a stimulus. Either mechanism could cause changes in the perception of a stimulus over time. One hundred twenty observers were tested in an illusion-decrement paradigm under exposure conditions that altered the amount of selective adaptation of specific neural channels. Observers were also measured on the magnitude of the transfer-of-decrement effect. Both decrement and transfer of decrement occurred, but there was no significant difference across exposure conditions. In addition, the pattern of transfer differed from that observed in selective adaptation paradigms. These results argue against a neural adaptation interpretation of illusion decrement.     

Does affect induce self-focused attention?

Despite growing evidence that depression is linked with self-focused attention, little is known about how depressed individuals become self-focused or, more generally, about what arouses self-focus in everyday life. Two experiments examined the hypothesis that affect itself induces self-focused attention. In Experiment 1, moods were manipulated with an imagination mood-induction procedure. Sad-induction Ss became higher in self-focus than did neutral-induction Ss. Experiment 2 replicated this effect for sad moods by means of a musical mood-induction procedure and different measures of self-focus. However, Experiment 2 failed to support the hypothesis that happy moods induce self-focus. The results have implications for mood-induction research, self-focused attention, and recent models of depression.     

Does “feeling down” mean seeing down? Depressive symptoms and vertical selective attention

Prior research reveals that the encoding of affective stimuli is biased in a metaphorically consistent manner (e.g., good = up; bad = down). For example, negative words are evaluated faster if they are presented in a low versus high vertical position. The present studies extended this view by investigating whether such biases also correlate with individual differences in emotional experience. Specifically, in two studies, we examined whether vertical metaphor would be useful in understanding negative affect as manifested in neuroticism and depressive symptoms. We found support for this premise. That is, the higher the neuroticism (Studies 1 and 2) or depressive symptoms (Study 2) of participants, the faster they were to respond to or detect lower (versus higher) spatial attention targets. These results suggest that negative affect in general, and depressive symptoms in particular, appear to bias selective attention in a direction that favors lower regions of physical space.     

Does mood influence the realism of confidence judgments?

Previous research has shown that mood affects cognition, but the extent to which mood affects meta-cognitive judgments is a relatively over-looked issue. In the current study we investigated how mood influences the degree of realism in participants' confidence judgments (based on an episodic memory task). Using music and film in combination, we successfully induced an elated mood in half of the participants, but failed to induce a sad mood in the other half. In line with previous research, the participants in both conditions were overconfident in their judgments. However, and contrary to our prediction, our data indicated that there was no difference in the realism of the confidence between the conditions. When relating this result to previous research, our conclusion is that there is no, or very little, influence of mood of moderate intensity on the realism of confidence judgments.     

Aging of attention: Does the ability to divide decline?

Previous research has yielded conflicting results regarding the relationship between adult age and the ability to divide attention between two concurrent tasks. At least some of the inconsistency is probably attributable to methodological variations, such as the manner in which divided-attention ability has been assessed, how single-task performance has been considered, and the degree of control over relative emphasis placed on each task. Two experiments employing procedures sensitive to these concerns were conducted in which a speeded decision task was performed during the retention interval of a letter-memory task. The results of both experiments indicated that there were relatively few age-related influences on dual-task performance vis-à-vis those on single-task performance.