Parallel processing of objects in a naming task.

The authors investigated whether speakers who named several objects processed them sequentially or in parallel. Speakers named object triplets, arranged in a triangle, in the order left, right, and bottom object. The left object was easy or difficult to identify and name. During the saccade from the left to the right object, the right object shown at trial onset (the interloper) was replaced by a new object (the target), which the speakers named. Interloper and target were identical or unrelated objects, or they were conceptually unrelated objects with the same name (e.g., bat [animal] and [baseball] bat). The mean duration of the gazes to the target was shorter when interloper and target were identical or had the same name than when they were unrelated. The facilitatory effects of identical and homophonous interlopers were significantly larger when the left object was easy to process than when it was difficult to process. This interaction demonstrates that the speakers processed the left and right objects in parallel. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention and facilitation: Converging information versus inadvertent reading in Stroop task performance.

Disagreement exists about whether color–word Stroop facilitation is caused by converging information (e.g., Cohen et al., 1990; Roelofs, 2003) or inadvertent reading (MacLeod & MacDonald, 2000). Four experiments tested between these hypotheses by examining Stroop effects on response time (RT) both within and between languages. Words cannot be read aloud to produce facilitation between languages. Dutch–English bilingual participants named color patches while trying to ignore Dutch or English color words presented at a wide range of preexposure and postexposure stimulus onset asynchronies. The color patches were named in Dutch (Experiments 1 and 2) or English (Experiments 3 and 4). In all experiments, Stroop facilitation and interference effects were obtained in mean RTs with similar time courses within and between languages. Facilitation was generally present throughout the entire RT distributions. These results suggest that Stroop interference and facilitation have a common locus within and between languages, supporting the converging information hypothesis of Stroop facilitation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The time course of name retrieval during multiple-object naming: Evidence from extrafoveal-on-foveal effects.

The goal of the study was to examine whether speakers naming pairs of objects would retrieve the names of the objects in parallel or in sequence. To this end, we recorded the speakers’ eye movements and determined whether the difficulty of retrieving the name of the 2nd object affected the duration of the gazes to the 1st object. Two experiments, which differed in the spatial arrangement of the objects, showed that the speakers looked longer at the 1st object when the name of the 2nd object was easy than when it was more difficult to retrieve. Thus, the easy 2nd-object names interfered more with the processing of the 1st object than the more difficult 2nd-object names. In the 3rd experiment, the processing of the 1st object was rendered more difficult by presenting it upside down. No effect of 2nd-object difficulty on the gaze duration for the 1st object was found. These results suggest that speakers can retrieve the names of a foveated and an extrafoveal object in parallel, provided that the processing of the foveated object is not too demanding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention, gaze shifting, and dual-task interference from phonological encoding in spoken word planning.

Controversy exists about whether dual-task interference from word planning reflects structural bottleneck or attentional control factors. Here, participants named pictures whose names could or could not be phonologically prepared, and they manually responded to arrows presented away from (Experiment 1), or superimposed onto, the pictures (Experiments 2 and 3); or they responded to tones (Experiment 4). Pictures and arrows/tones were presented at stimulus onset asynchronies of 0, 300, and 1,000 ms. Earlier research showed that vocal responding hampers auditory perception, which predicts earlier shifts of attention to the tones than to the arrows. Word planning yielded dual-task interference. Phonological preparation reduced the latencies of picture naming and gaze shifting. The preparation benefit was propagated into the latencies of the manual responses to the arrows but not to the tones. The malleability of the interference supports the attentional control account. This conclusion was corroborated by computer simulations showing that an extension of WEAVER++ (A. Roelofs, 2003) with assumptions about the attentional control of tasks quantitatively accounts for the latencies of vocal responding, gaze shifting, and manual responding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual attention and word recognition in Stroop color naming: Is word recognition "automatic?"

In Stroop color naming, color targets were accompanied by a color word or a color word plus a neutral word that reduces or "dilutes" the Stroop effect. Abrupt-onset cues called the focus of attention to one stimulus or another. Cuing influenced the size of the Stroop effect but never eliminated it. Unlike the Stroop effect itself, Stroop dilution from the neutral word could be eliminated, by cuing the color word. Focusing visual attention on the color word protected it from Stroop dilution; focusing visual attention on the neutral word did not prevent Stroop interference. Thus, spatial attention is a modulator, protecting visual data from crosstalk, but a word need not be the focus of visual attention to be recognized. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Focused and shifting attention in children with heavy prenatal alcohol exposure.

Attention deficits are a hallmark of the teratogenic effects of alcohol. However, characterization of these deficits remains inconclusive. Children with heavy prenatal alcohol exposure and nonexposed controls were evaluated using a paradigm consisting of three conditions: visual focus, auditory focus, and auditory-visual shift of attention. For the focus conditions, participants responded manually to visual or auditory targets. For the shift condition, participants alternated responses between visual targets and auditory targets. For the visual focus condition, alcohol-exposed children had lower accuracy and slower reaction time for all intertarget intervals (ITIs), while on the auditory focus condition, alcohol-exposed children were less accurate but displayed slower reaction time only on the longest ITI. Finally, for the shift condition, the alcohol-exposed group was accurate but had slowed reaction times. These results indicate that children with heavy prenatal alcohol exposure have pervasive deficits in visual focused attention and deficits in maintaining auditory attention over time. However, no deficits were noted in the ability to disengage and reengage attention when required to shift attention between visual and auditory stimuli, although reaction times to shift were slower. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

When observing gaze shifts of others enhances object desirability.

The present research explored when observing gaze shifts of another person, involving both the observer and a specific object, enhances desirability of the gazed-at object. Specifically, we offer an initial attempt to test the idea that a three-step sequence consisting of direct gaze at the observer, followed by object-directed gaze and then by direct gaze at the observer, cues the desirability of an object to the observer and hence increases the perceived desirability of the gazed-at object. We examined this hypothesis in three experiments by manipulating eye-gaze shifts and including a no-gaze control condition. In line with our prediction, results showed that the dynamic sequence of gaze shifts indeed increases perceived object desirability. These findings provide new evidence that a sequence of gaze behavior involving the observer and an object plays an important role in influencing affective evaluation of objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Active gaze, visual look-ahead, and locomotor control.

The authors examined observers steering through a series of obstacles to determine the role of active gaze in shaping locomotor trajectories. Participants sat on a bicycle trainer integrated with a large field-of-view simulator and steered through a series of slalom gates. Steering behavior was determined by examining the passing distance through gates and the smoothness of trajectory. Gaze monitoring revealed which slalom targets were fixated and for how long. Participants tended to track the most immediate gate until it was about 1.5 s away, at which point gaze switched to the next slalom gate. To probe this gaze pattern, the authors then introduced a number of experimental conditions that placed spatial or temporal constraints on where participants could look and when. These manipulations resulted in systematic steering errors when observers were forced to use unnatural looking patterns, but errors were reduced when peripheral monitoring of obstacles was allowed. A steering model based on active gaze sampling is proposed, informed by the experimental conditions and consistent with observations in free-gaze experiments and with recommendations from real-world high-speed steering. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Should I stay or should I go? Attentional disengagement from visually unique and unexpected items at fixation.

Distinctive aspects of a scene can capture attention even when they are irrelevant to one’s goals. The authors address whether visually unique, unexpected, but task-irrelevant features also tend to hold attention. Observers searched through displays in which the color of each item was irrelevant. At the start of search, all objects changed color. Critically, the foveated item changed to an unexpected color (it was novel), became a color singleton (it was unique), or both. Saccade latency revealed the time required to disengage overt attention from this object. Singletons resulted in longer latencies, but only if they were unexpected. Conversely, unexpected items only delayed disengagement if they were singletons. Thus, the time spent overtly attending to an object is determined, at least in part, by task-irrelevant stimulus properties, but this depends on the confluence of expectation and visual salience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Early, Involuntary Top-Down Guidance of Attention From Working Memory.

Four experiments explored the interrelations between working memory, attention, and eye movements. Observers had to identify a tilted line amongst vertical distractors. Each line was surrounded by a colored shape that could be precued by a matching item held in memory. Relative to a neutral baseline, in which no shapes matched the memory item, search was more efficient when the memory cue matched the shape containing the target, and it was less efficient when the cued stimulus contained a distractor. Cuing affected the shortest reaction times and the first saccade in search. The effect occurred even when the memory cue was always invalid but not when the cue did not have to be held in memory. There was also no evidence for priming effects between consecutive trials. The results suggest that there can be early, involuntary top-down directing of attention to a stimulus matching the contents of working memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attending to Eye Movements and Retinal Eccentricity: Evidence for the Activity Distribution Model of Attention Reconsidered.

When testing between spotlight and activity distribution models of visual attention, D. LaBerge, R. L. Carlson, J. K. Williams, and B. G. Bunney (1997) used an experimental paradigm in which targets are embedded in 3 brief displays. This paradigm, however, may be confounded by retinal eccentricity effects and saccadic eye movements. When the retinal eccentricities of the targets are equated and eye position is monitored, the pattern of results reported by LaBerge et al., which supported the activity distribution model, is not found. This result underscores the importance of considering targets' eccentricity and people's inclination to make saccadic eye movements in certain types of visual cognition tasks. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Attention to gaze and emotion in schizophrenia.

Objective: Individuals with schizophrenia have difficulty interpreting social and emotional cues such as facial expression, gaze direction, body position, and voice intonation. Nonverbal cues are powerful social signals but are often processed implicitly, outside the focus of attention. The aim of this research was to assess implicit processing of social cues in individuals with schizophrenia. Method: Patients with schizophrenia or schizoaffective disorder and matched controls performed a primary task of word classification with social cues in the background. Participants were asked to classify target words (LEFT/RIGHT) by pressing a key that corresponded to the word, in the context of facial expressions with eye gaze averted to the left or right. Results: Although facial expression and gaze direction were irrelevant to the task, these facial cues influenced word classification performance. Participants were slower to classify target words (e.g., LEFT) that were incongruent to gaze direction (e.g., eyes averted to the right) compared to target words (e.g., LEFT) that were congruent to gaze direction (e.g., eyes averted to the left), but this only occurred for expressions of fear. This pattern did not differ for patients and controls. Conclusion: The results showed that threat-related signals capture the attention of individuals with schizophrenia. These data suggest that implicit processing of eye gaze and fearful expressions is intact in schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention, automaticity, and developmental dyscalculia.

People suffering from developmental dyscalculia (DD) show an abnormal pattern of the size congruity effect. They do not display a facilitation component in a numerical Stroop task. In this task, participants are presented with 2 digits that differ both in physical size and numerical value, and they have to compare the digits while ignoring one of the dimensions. The present study examined performance of those with DD and control participants in the numerical Stroop task under cognitive load. The no-load condition replicated previous findings (i.e., lack of facilitation in the physical task for the DD group). Load had opposite effects on interference and facilitation. Load eliminated facilitation and increased interference in the control group. Load increased interference only in the physical task in the DD group. The opposite effect of load on facilitation and interference suggests that these components are related to different cognitive mechanisms. The fact that load produced a DD-like pattern in the control group could suggest that individuals with DD suffer from difficulty in recruiting attention in addition to the deficits in numerical processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Trade-offs between gaze and working memory use.

Eye movements during natural tasks suggest that observers do not use working memory to capacity but instead use eye movements to acquire relevant information immediately before needed. Results here however, show that this strategy is sensitive to memory load and to observers' expectations about what information will be relevant. Depending upon the predictability of what object features would be needed in a brick sorting task, subjects spontaneously modulated the order in which they sampled and stored visual information using working memory more when the task was predictable and reverting to a just-in-time strategy when the task was unpredictable and the memory load was higher. This self organization was evidenced by subjects' sequence of eye movements and also their sorting decisions following missed feature changes. These results reveal that attentional selection, fixations, and use of working memory reflect a dynamic optimization with respect to a set of constraints, such as task predictablity and memory load. They also reveal that change blindness depends critically on the local task context, by virtue of its influence on the information selected for storage in working memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stroop Tasks Reveal Abnormal Selective Attention Among Psychopathic Offenders.

Selective attention among offenders with psychopathy was investigated using 3 Stroop paradigms: a standard color-word (CW) Stroop, a picture-word (PW) Stroop, and a color-word Stroop in which the word and color were spatially separated (separated CW). Consistent with "overselective" attention, offenders with psychopathy displayed reduced Stroop interference on the separated CW and PW tasks relative to offenders who were not psychopathic. However, offenders with psychopathy displayed normal Stroop interference on the standard CW Stroop. Further, the reduced interference of offenders with psychopathy on the separated CW Stroop was accompanied by normal facilitation. These findings suggest a circumscribed attentional deficit in psychopathy that hinders the use of unattended information that is (a) not integrated with deliberately attended information and (b) not compatible with current goal-directed behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory for where, but not what, is used during visual search.

Although the role of memory in visual search is debatable, most researchers agree with a limited-capacity model of memory in visual search. The authors demonstrate the role of memory by replicating previous findings showing that visual search is biased away from old items (previously examined items) and toward new items (nonexamined items). Furthermore, the authors examined the type of memory representations used to bias search by changing an item's individuating feature or location during search. Changing the individuating feature of an item did not disrupt normal search biases. However, when the location of an item changed, normal search biases were disrupted. These results suggest that memory used in visual search is based on items' locations rather than their identity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Toward a perceptual-span theory of distributed processing in reading: A reply to Rayner, Pollatsek, Drieghe, Slattery, and Reichle (2007).

K. Rayner, A. Pollatsek, D. Drieghe, T. J. Slattery, and E. D. Reichle (see record 2007-11669-010) argued that the R. Kliegl, A. Nuthmann, and R. Engbert (see record 2006-01956-002) corpus-analytic evidence for distributed processing during reading should not be accepted because (a) there might be problems of multicollinearity, (b) the distinction between content and function words and the skipping status of neighboring words was ignored, and (c) there are inconsistencies with experimental results. Reanalyses with linear mixed-effect models demonstrate that (a) regression coefficients are stable across 9 samples, (b) lexical status and skipping status (and their interactions) are highly significant but do not account for the effects of word frequency for content and for function words, and (c) there is strong evidence for lexical processing of content words while fixating function words to the left of them. A critical result about fixation durations prior to skipped words is replicated in an experiment. The distinction between correlational analyses and well-controlled experiments and questions about generalizability of results are discussed. The author argues for a complementary role of corpus analysis, computational modeling, and experiments in reading research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Age-related deficits in auditory confrontation naming.

The naming of manipulable objects in older and younger adults was evaluated across auditory, visual, and multisensory conditions. Older adults were less accurate and slower in naming across conditions, and all subjects were more impaired and slower to name action sounds than pictures or audiovisual combinations. Moreover, there was a sensory by age group interaction, revealing lower accuracy and increased latencies in auditory naming for older adults unrelated to hearing insensitivity but modest improvement to multisensory cues. These findings support age-related deficits in object action naming and suggest that auditory confrontation naming may be more sensitive than visual naming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Is position "special" in visual attention? Evidence that top-down processes guide visual selection.

The role of spatial position in selective visual processing has been the source of recent debate. The present study, using undergraduates, attempted to reconcile various findings by exploring the influence of top-down processes (task instructions) while explicitly controlling for eye movements. Exp 1 demonstrated there was no inherent selection bias for stimuli similar to those used by A. H. C. van der Heijden et al (1996), suggesting that the tendency to select according to colour found by van der Heijden et al was due to task demands. Exp 2 further established the role of top-down factors by replicating the results of van der Heijden et al with the current authors' stimuli. Exp 3 demonstrated that selection can be switched from colour to position by changing the demands of the task. These results suggest that selection may be accounted for by task demands (e.g., instructions) with no priority access for position information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Attention switching during scene perception: How goals influence the time course of eye movements across advertisements.

Eye movements across advertisements express a temporal pattern of bursts of respectively relatively short and long saccades, and this pattern is systematically influenced by activated scene perception goals. This was revealed by a continuous-time hidden Markov model applied to eye movements of 220 participants exposed to 17 ads under a free-viewing condition, and a scene-learning goal (ad memorization), a scene-evaluation goal (ad appreciation), a target-learning goal (product learning), or a target-evaluation goal (product evaluation). The model reflects how attention switches between two states--local and global--expressed in saccades of shorter and longer amplitude on a spatial grid with 48 cells overlaid on the ads. During the 5- to 6-s duration of self-controlled exposure to ads in the magazine context, attention predominantly started in the local state and ended in the global state, and rapidly switched about 5 times between states. The duration of the local attention state was much longer than the duration of the global state. Goals affected the frequency of switching between attention states and the duration of the local, but not of the global, state. (PsycINFO Database Record (c) 2010 APA, all rights reserved)