Interpretation of homophones related to threat in anxiety states

In previous studies, we have established that anxiety states are characterized by an attentional bias that favors the processing of threatening stimuli. In the present study we extend this finding to ambiguous stimuli, specifically, homophones with spellings that correspond to either a threatening or a neutral meaning. As predicted, clinically anxious subjects used the threatening spellings relatively more than did controls, whereas recovered subjects were intermediate in this respect. Threatening words were associated with greater skin conductance responses than were neutral words, but the groups did not differ in their electrodermal reactions to homophones. We take these findings as evidence that, although the different meanings of ambiguous stimuli may be processed in parallel by all subjects, an interpretive bias operates such that anxiety-prone individuals tend to become preferentially aware of the more threatening meaning of such events.     

Aging and goal-directed emotional attention: distraction reverses emotional biases

Previous findings reveal that older adults favor positive over negative stimuli in both memory and attention (for a review, see Mather & Carstensen, 2005). This study used eye tracking to investigate the role of cognitive control in older adults' selective visual attention. Younger and older adults viewed emotional-neutral and emotional-emotional pairs of faces and pictures while their gaze patterns were recorded under full or divided attention conditions. Replicating previous eye-tracking findings, older adults allocated less of their visual attention to negative stimuli in negative-neutral stimulus pairings in the full attention condition than younger adults did. However, as predicted by a cognitive-control-based account of the positivity effect in older adults' information processing tendencies (Mather & Knight, 2005), older adults' tendency to avoid negative stimuli was reversed in the divided attention condition. Compared with younger adults, older adults' limited attentional resources were more likely to be drawn to negative stimuli when they were distracted. These findings indicate that emotional goals can have unintended consequences when cognitive control mechanisms are not fully available.     

Why does natural scene categorization require little attention? Exploring attentional requirements for natural and synthetic stimuli

It was recently demonstrated that detecting target objects (e.g., animals) in natural scenes can be done in a dual-task paradigm, in the near absence of spatial attention. Under the same conditions, subjects were unable to perform apparently simpler tasks involving synthetic stimuli (e.g., discriminating randomly rotated Ts and Ls, or a bisected colour disc and its mirror image). Classical theories predict that attention is more critical for the recognition of complex stimuli that cannot be easily separated on a single feature dimension. Therefore, these puzzling results have raised a number of questions. If it is not the complexity of a stimulus, what then determines the recognition task's attentional requirements? How does this differ between natural and artificial stimuli? What can these observations tell us about the mechanism of natural scene processing as well as its relation to attention? Here we show that removing colour information, or doubling the amount of information to be analysed, failed to make the natural scene categorization tasks significantly more “attention demanding”. Conversely, increasing discriminability or predictability did not diminish the need for attention in the case of synthetic stimuli. However, when the familiar letters, such as Ts or Ls, were presented upright, full attention was no longer required for discrimination. This suggests that familiarity and meaningfulness might be among the factors that determine attentional requirements for both natural and synthetic stimuli.     

Effects of level of processing on memory for affectively valenced words

In this study we tested whether subjects remember affectively valenced stimuli better than neutral stimuli when their attention is not focused on the affective charge of the stimuli during encoding. We tested memory for positive, negative, and neutral words in three memory tasks and using two encoding conditions (physical and semantic). Our results show that subjects remember affectively valenced stimuli better than neutral stimuli when they encode them according to their emotional content as well as to other features of the stimuli. However, although both positive and negative words are better remembered than neutral ones when semantically encoded, only positive words are better remembered than neutral ones when physically encoded. These results suggest that the affective charge of a stimulus (especially when positive) can affect retention even when a subject's attention has not focused on it during encoding.     

Simultaneous auditory and tactile information processing

Subjects were required to perform perceptual tasks when stimuli were presented simultaneously in the auditory and tactile modalities and when they were presented in one of the modalities alone. The results indicated that when the demands on cognitive processes are small, auditory and tactile stimuli presented simultaneously can be processed as well as when stimuli are presented in only one modality. In a task which required a large amount of cognitive processing, it became difficult for subjects to maintain high levels of performance in both modalities and the distribution of attention became an important determinant of performance. The data were consistent with a theory that cognitive, but not perceptual, processing is disrupted when subjects have difficulty performing two perceptual tasks simultaneously.     

Chromatic information processing

The investigation of visual processing mediated solely by chromatic information requires conditions preventing a subject's use of the luminance differences normally accompanying a chromatic change. In Experiment 1, which involved a discriminative reaction time (RT) task, chromatic and white stimuli of the same luminance were presented on a dimmer achromatic background. Subjects were instructed to respond only to the chromatic stimuli. RT was slowest at 570 nm and somewhat faster to short wavelengths than to long wavelengths. In Experiment 2, which compared two discriminative RT tasks, RT was faster when subjects responded to color than when they responded to white. Experiments 3 and 4 demonstrated that a brighter white surround decreased the perceived brightness of chromatic stimuli as well as their perceptual similarity to white, but did not affect RT. The results are discussed in terms of the response strength of the chromatic processing channel.     

Attention,Memory, Intrusive Thoughts,and Acceptance in PTSD: An Update on the Empirical Literature for Clinicians

Information processing theory suggests that cognitive changes following trauma are common and hypothesized to have an impact on attention, memory, and intrusive thoughts. There is an ever-expanding empirical literature where cognitive features of posttraumatic stress disorder (PTSD) are being explored. However, it can sometimes be difficult for front-line clinicians to stay abreast of this literature and how it impacts the treatment s/he provides. The goal of this paper is to provide an overview of some recent basic and applied research on information processing in PTSD and the implications of these findings for cognitive-behavioral clinicians. In particular, we explore recent findings regarding attention, memory, intrusive thoughts/thought suppression, and acceptance as they relate to clinical work in patients with PTSD.     

The role of attentional biases in PTSD: is it interference or facilitation?

Although attentional biases have been demonstrated in individuals with posttraumatic stress disorder (PTSD), the cognitive methodologies used have not allowed for disambiguation of two types of attentional biases. It remains unclear if PTSD involves difficulty disengaging attention from threatening stimuli (interference) or facilitated detection. To differentiate between attentional interference and facilitation, 57 male Vietnam-era veterans (30 High PTSD and 27 Low PTSD) completed a visual search task with a lexical decision component. High PTSD veterans who engaged in the interference task first showed increased interference to threat-relevant words relative to Low PTSD veterans. However, no evidence was found for facilitated detection of threatening stimuli in PTSD.     

A further examination of attentional effects in the phonemic restoration illusion

Models of how listeners understand speech must specify the types of representations that are computed, the nature of the flow of information, and the control structures that modify performance. Three experiments are reported that focus on the control processes in speech perception. Subjects in the experiments tried to discriminate stimuli in which a phoneme had been replaced with white noise from stimuli in which white noise was merely superimposed on a phoneme. In the first two experiments, subjects practiced the discrimination for thousands of trials but did not improve, suggesting that they have poor access to low-level representations of the speech signal. In the third experiment, each (auditory) stimulus was preceded by a visual cue that could potentially be used to focus attention in order to enhance performance. Only subjects who received information about both the identity of the impending word and the identity of the critical phoneme showed enhanced discrimination. Other cues, including syllabic plus phonemic information, were ineffective. The results indicate that attentional control of processing is difficult but possible, and that lexical representations play a central role in the allocation of attention.     

Impulsivity and perception: individual differences in the processing of the local and global dimensions of stimuli

There appears to be an association between a "global" mode of perceptual processing and a cluster of personality traits, one of which is impulsivity. The goal of the present study was to clarify this relationship. Subjects differing in impulsivity (as measured by a self-report inventory) performed speeded cardsorting tasks. They sorted stimuli consisting of large letters made up of smaller letters. Highly impulsive subjects had no more difficulty than other subjects in ignoring the large, "global," letters when they tried to attend to the smaller, "local," letters of which they were composed, nor were they more vulnerable than other subjects to Stroop-like response interference produced by the global letters. High impulsives did have particular difficulty when the task required that they integrate the information provided by the local and global letters. This finding can be explained in terms of individual differences in the value placed on speed relative to accuracy in information processing.     

Depression and Problem-Solving Performance on a Fault-Diagnosis Task

Dysphoric and control undergraduates selected on the basis of Beck Depression Inventory scores were compared on a problem-solving task involving fault-diagnosis. The stimuli were wiring diagrams showing boxes or units connected to indicators, and the aim was to diagnose which one of the units was faulty. Dysphoric subjects did not differ from controls on problems requiring them to use the information available at the outset of the problem to identify all the potentially faulty units. They were impaired relative to controls in testing connections that they believed to be potentially faulty until the faulty unit was diagnosed; they made more repetition errors, carried out more redundant tests, and were slower than controls, although the groups did not differ in the number of correct solutions achieved. The findings are discussed in terms of theoretical models that posit impaired strategic processing in depression.     

刷微博，让焦虑的人更焦虑——特质焦虑对青少年注意情绪刺激的影响

采用自由观看眼动追踪范式,考察特质焦虑青少年在观看情绪面孔图片过程中的眼动轨迹。结果发现,高特质焦虑组对愤怒和恐惧面孔的首次注视到达时间（TFF）较快,首次注视持续时间（TFD）较短;低特质焦虑组对愤怒和恐惧面孔的TFF虽然稍早于平静面孔,但差异不显著。在刺激呈现1000ms之后,高特质焦虑组对愤怒和恐惧面孔的注视次数（FC）较多,平均注视持续时间（AFD）较短。低特质焦虑组对愤怒和恐惧面孔的FC较少,AFD较长;这就表明,高特质焦虑青少年在认知加工早期对威胁性刺激注意定向加速,没有注意解除困难,呈现“浅尝辄止”现象。而在认知加工晚期,他们则对威胁性刺激存在“反刍”现象。     

Segmentation and speech perception in relation to reading skill: a developmental analysis

The present paper examines the processing of speech by dyslexic readers and compares their performance with that of age-matched (CA) and reading-ability-matched (RA) controls. In Experiment 1, subjects repeated single-syllable stimuli (words and nonwords) presented either in a favorable signal-to-noise ratio or with noise masking. Noise affected all subjects to the same extent. Dyslexic children performed as well as controls when repeating high-frequency words, but they had difficulty relative to CA-controls with low-frequency words and relative to both CA- and RA-controls when repeating nonwords. In Experiments 2 and 3, subjects made auditory lexical decisions about the stimuli presented in Experiment 1. Dyslexics performed less well than CA-controls, gaining similar scores to RA-controls. Thus, their difficulty in repeating low-frequency words could be reinterpreted as a difficulty with nonword repetition. Taken together, these results suggest that dyslexics have difficulty with the nonlexical procedures (including phoneme segmentation) involved in verbal repetition. One consequence is that they take longer to consolidate "new" words; verbal memory and reading processes are also compromised.     

Mechanisms of visual threat detection in specific phobia

People with anxiety or stress-related disorders attend differently to threat-relevant compared with non-threat stimuli, yet the temporal mechanisms of differential allocation of attention are not well understood. We investigated two independent mechanisms of temporal processing of visual threat by comparing spider-phobic and non-fearful participants using a rapid serial visual presentation task. Consistent with prior literature, spider phobics, but not non-fearful controls, displayed threat-specific facilitated detection of spider stimuli relative to negative stimuli and neutral stimuli. Further, signal detection analyses revealed that facilitated threat detection in spider-phobic participants was driven by greater sensitivity to threat stimulus features and a trend towards a lower threshold for detecting spider stimuli. However, phobic participants did not display reliably slowed temporal disengagement from threat-relevant stimuli. These findings advance our understanding of threat feature processing that might contribute to the onset and maintenance of symptoms in specific phobia and disorders that involve visual threat information more generally.     

Task relevance modulates processing of distracting emotional stimuli

Numerous studies have claimed that emotional stimuli are able to capture attention automatically when presented outside the main focus of attention. In the current study this claim was tested by using task-relevant and task-irrelevant emotional stimuli. Specifically, in two experiments the effect of emotional stimuli presented in the periphery of attention was tested by using a flanker task. Results showed that emotional stimuli did not capture attention in an unconditional manner. Emotional distracting stimuli created interference only when they were relevant to the task. The findings suggest that "task relevance" is determined by (a) task requirements, and/or (b) target characteristics. The current results have implications for the concept of cognitive load and automaticity of processing emotional stimuli.     

Early information processing among infants with and without spina bifida

This study focuses on the development of early visual information processing among infants with spina bifida (SB) compared to typically developing infants using the habituation–dishabituation paradigm. Analyses were conducted in two stages. First infants were evaluated to determine if 18-month old infants (SB = 47; Control = 40) differed in their ability to shift attention and habituate to two female faces, as well as their responses to composite and novel stimuli. Second, relations between these variables and infant motor and mental functioning were evaluated. The results of the study indicated that difficulties with visual attention skills can be detected as early as 18 months of age among infants with SB. Infants with SB differed significantly from controls on attention getting. Although there were no differences found on habituation and composite tasks, infants with SB differed significantly from controls on their ability to dishabituate. Implications are discussed.     

Intact emotion–cognition interaction in schizophrenia patients and first-degree relatives: Evidence from an emotional antisaccade task

Schizophrenia patients have deficits in cognitive control as well as in a number of emotional domains. The antisaccade task is a measure of cognitive control that requires the inhibition of a reflex-like eye movement to a peripheral stimulus. Antisaccade performance has been shown to be modulated by the emotional content of the peripheral stimuli, with emotional stimuli leading to higher error rates than neutral stimuli, reflecting an implicit emotion processing effect. The aim of the present study was to investigate the impact on antisaccade performance of threat-related emotional facial stimuli in schizophrenia patients, first-degree relatives of schizophrenia patients and healthy controls. Fifteen patients, 22 relatives and 26 controls, matched for gender, age and verbal intelligence, carried out an antisaccade task with pictures of faces displaying disgusted, fearful and neutral expressions as peripheral stimuli. We observed higher antisaccade error rates in schizophrenia patients compared to first-degree relatives and controls. Relatives and controls did not differ significantly from each other. Antisaccade error rate was influenced by the emotional nature of the stimuli: participants had higher antisaccade error rates in response to fearful faces compared to neutral and disgusted faces. As this emotional influence on cognitive control did not differ between groups we conclude that implicit processing of emotional faces is intact in patients with schizophrenia and those at risk for the illness.     

Conceptual and perceptual priming and dissociation in chronic posttraumatic stress disorder

Cognitive models of posttraumatic stress disorder (PTSD) assert that memory processes play a significant role in PTSD (see e.g., Ehlers & Clark, 2000). Intrusive reexperiencing in PTSD has been linked to perceptual processing of trauma-related material with a corresponding hypothesized lack of conceptual processing. In an experimental study that included clinical participants with and without PTSD (N = 50), perceptual priming and conceptual priming for trauma-related, general threat, and neutral words were investigated in a population with chronic trauma-induced complaints as a result of the Troubles in Northern Ireland. The study used a new version of the word-stem completion task (Michael, Ehlers, & Halligan, 2005) and a word-cue association task. It also assessed the role of dissociation in threat processing. Further evidence of enhanced perceptual priming in PTSD for trauma stimuli was found, along with evidence of lack of conceptual priming for such stimuli. Furthermore, this pattern of priming for trauma-related words was associated with PTSD severity, and state dissociation and PTSD group made significant contributions to predicting perceptual priming for trauma words. The findings shed light on the importance of state dissociation in trauma-related information processing and posttraumatic symptoms.     

Memory scanning of shapes,colors, and compounds: A comparison of retarded and nonretarded adults

Three experiments were performed to assess memory scanning of shapes, colors, and shape-color compounds by retarded and nonretarded people. Attributes comprising compounds provided either redundant or nonredundant information. Large retarded-nonretarded differences in reaction time were obtained. In contrast to previous reports of slow scanning of digits and nonsense shapes by retarded people, scan rates for shapes and colors did not differ between groups. Retarded subjects were not characterized by a deficient scan rate. Although compound stimuli required twice as many attributes in their repersentation as did simple stimuli, they were not scanned more slowly, indicating that per item scan rate is not determined by the number of attributes required to define each item. Both groups were able to exploit redundant relevant information to achieve faster processing than in simple conditions. Decision rules for rejecting compound stimuli comprised one, two, or more binary tests. Groups did not differ in speed of performing elementary binary test(s).