Exploring an integrative model of infant behavior: what is the relationship among temperament, sensory processing, and neurobehavioral measures?

Traditionally, developmental psychology, occupational/physical therapy, and behavioral pediatrics view similar infant behaviors from temperament, sensory processing, or neurobehavioral theoretical perspectives. This study examined the relations between similar and unique summary scores of three infant assessments (Early Infancy Temperament Questionnaire - EITQ, the Infant Sensory Profile - ISP, and the NICU Network Neurobehavioral Scale - NNNS) in a healthy sample of 100, one-month-old infants. A Principal Components Analysis of selected subscale scores derived from the three assessments suggested a three-factor model. Temperament and sensory summary scores had the strongest relations on two factors: Sensory-Affective Reactivity and Engagement. A third factor had strong relations between state regulation and motor competence. This new integrative model also validates an existing model and expands explanation of infant behavior across disciplines and methods which have significant implications for assessment, intervention, and management practices.     

Are historic years understood as numbers or events? An fMRI study of numbers with semantic associations

While numbers generally cue processing of quantity or order, they can also contain semantic information, as in the case of historic years (e.g., “1492” calls forth associations of Columbus sailing the ocean blue). Whether these dates are processed as quantities or events may depend on the context in which they occur. We examined such “ambiguous number” processing in two different contexts using a paired-comparison task, recording both behavioral responses and brain activity. Participants were either asked to think of all items as numbers and to choose the larger number, or were told to treat the comparators as events and to choose the later event. Behaviorally, all events showed a normal distance effect, establishing that they may be understood and compared in an ordinal sequence. Functional magnetic resonance imaging (fMRI) demonstrated significant differences between years when treated as numbers versus as events. Dates in both contexts shared activity in parietal lobe regions previously implicated in number processing. Dates as numbers showed no extra-numeric activity, while dates thought of as events evoked activity in temporal semantic processing and frontal semantic retrieval areas. These differences suggest that extra-numeric information may be easily accessed and incorporated during processing when supported by even a weak context. This work supports previous studies showing a dissociation between quantity and meaning, and illustrates the brain areas involved in these different aspects.     

Does a sensory processing deficit explain counting accuracy on rapid visual sequencing tasks in adults with and without dyslexia?

The experiments conducted aimed to investigate whether reduced accuracy when counting stimuli presented in rapid temporal sequence in adults with dyslexia could be explained by a sensory processing deficit, a general slowing in processing speed or difficulties shifting attention between stimuli. To achieve these aims, the influence of the inter-stimulus interval (ISI), stimulus duration, and sequence length were evaluated in two experiments. In the first that used skilled readers only, significantly more errors were found with presentation of long sequences when the ISI or stimulus durations were short. Experiment 2 used a wider range of ISIs and stimulus durations. Compared to skilled readers, a group with dyslexia had reduced accuracy on two-stimulus sequences when the ISI was short, but not when the ISI was long. Although reduced accuracy was found on all short and long sequences by the group with dyslexia, when performance on two-stimulus sequences was used as an index of sensory processing efficiency and controlled, group differences were found with presentation of stimuli of short duration only. We concluded that continuous, repetitive stimulation to the same visual area can produce a capacity limitation on rapid counting tasks in all readers when the ISIs or stimulus durations are short. While reduced accuracy on rapid sequential counting tasks can be explained by a sensory processing deficit when the stimulus duration is long, slower processing speed in the group with dyslexia explains the greater inaccuracy found as sequence length is increased when the stimulus duration is short.     

Do conscious perception and unconscious processing rely on independent mechanisms? A meta-contrast study

There is currently no consensus regarding what measures are most valid to demonstrate perceptual processing without awareness. Likewise, whether conscious perception and unconscious processing rely on independent mechanisms or lie on a continuum remains a matter of debate. Here, we addressed these issues by comparing the time courses of subjective reports, objective discrimination performance and response priming during meta-contrast masking, under similar attentional demands. We found these to be strikingly similar, suggesting that conscious perception and unconscious processing cannot be dissociated by their time course. Our results also demonstrate that unconscious processing, indexed by response priming, occurs, and that objective discrimination performance indexes the same conscious processes as subjective visibility reports. Finally, our results underscore the role of attention by showing that how much attention the stimulus receives relative to the mask, rather than whether processing is measured by conscious discrimination or by priming, determines the time course of meta-contrast masking.     

Differentiating intolerance of uncertainty from three related but distinct constructs

Individual differences in uncertainty have been associated with heightened anxiety, stress and approach-oriented coping. Intolerance of uncertainty (IU) is a trait characteristic that arises from negative beliefs about uncertainty and its consequences. Researchers have established the central role of IU in the development of problematic worry and maladaptive coping, highlighting the importance of this construct to anxiety disorders. However, there is a need to improve our understanding of the phenomenology of IU. The goal of this paper was to present hypotheses regarding the similarities and differences between IU and three related constructs – intolerance of ambiguity, uncertainty orientation, and need for cognitive closure – and to call for future empirical studies to substantiate these hypotheses. To assist with achieving this goal, we conducted a systematic review of the literature, which also served to identify current gaps in knowledge. This paper differentiates these constructs by outlining each definition and general approaches to assessment, reviewing the existing empirical relations, and proposing theoretical similarities and distinctions. Findings may assist researchers in selecting the appropriate construct to address their research questions. Future research directions for the application of these constructs, particularly within the field of clinical and health psychology, are discussed.     

Negative cognitive style and looming cognitive style synergistically predict stress generation

There is a growing body of evidence that suggests that cognitive vulnerabilities to depression or anxiety may lead individuals to generate negative interpersonal life events. However, there has been no study to date that examines the effects of co-occurring vulnerabilities to depression and anxiety. In a sample of 304 participants, we examined the potential interaction of co-occurring negative cognitive style, a vulnerability to depression and looming cognitive style, vulnerability to anxiety. Results indicate that co-occurring cognitive vulnerabilities synergistically predict higher levels of negative interpersonal life events six weeks later, even when controlling for initial levels of stressful life events and symptoms of depression and anxiety. Thus, co-occurring vulnerabilities may have stronger stress generating effects than would be expected from the additive effects of each vulnerability considered separately. This finding highlights the importance of examining cognitive vulnerabilities as interactive effects rather than as individual vulnerabilities.     

Vulnerability-specific stress generation: an examination of depressogenic cognitive vulnerability across multiple domains

Background and Objectives: Although there is supporting evidence for the stress generation hypothesis (i.e., the tendency for depression-prone individuals to experience more negative dependent events influenced by their behaviors and characteristics), additional research is required to advance current understanding of the specific types of dependent events relevant to this effect. The present study elaborated on the stress generation hypothesis, in which the content of negative dependent events experienced by individuals is contingent upon, and matches, the nature of their particular vulnerabilities. This extension was tested within the context of Cole's competency-based model of depression. Design: Participants (n = 185) were assessed at two time-points separated by a four-month interval. Methods: Self-perceived competence in academic, social, and appearance domains at the initial time-point were examined in relation to negative life events prospectively occurring over the four-month follow-up period, assessed using the “contextual threat” method. Results: Partial support was obtained for vulnerability-specific stress generation. Stress-generation specificity was found for self-perceived competence in appearance and academic domains, but not for self-perceived social competence. Conclusions: The current findings are consistent with the possibility of a more complex relation between self-perceived social competence and domain-congruent stress generation. Individuals may be more likely to experience negative dependent events in domains matching their specific vulnerabilities.     

Response to Algarabel et al., 2012 “Recognition memory deficits in mild cognitive impairment”. Reconsidering claims of familiarity disruptions in mild cognitive impairment

There is some debate over the relative impairment of recollection and familiarity in mild cognitive impairment (MCI). A recent publication by Algarabel et al. (2012, Recognition memory deficits in mild cognitive impairment, Aging, Neuropsychology, and Cognition, 19, 608–619) claims to undermine previous studies reporting preserved familiarity in patients with MCI. Here, we respond to their main criticisms, concluding that they are not sufficiently supported by the data presented. The role of recollection and familiarity in MCI remains unresolved and further work will be required to disentangle the mixed literature.     

The impact of aging and hearing status on verbal short-term memory

The aim of this study is to assess the impact of hearing status on age-related decrease in verbal short-term memory (STM) performance. This was done by administering a battery of verbal STM tasks to elderly and young adult participants matched for hearing thresholds, as well as to young normal-hearing control participants. The matching procedure allowed us to assess the importance of hearing loss as an explanatory factor of age-related STM decline. We observed that elderly participants and hearing-matched young participants showed equal levels of performance in all verbal STM tasks, and performed overall lower than the normal-hearing young control participants. This study provides evidence for recent theoretical accounts considering reduced hearing level as an important explanatory factor of poor auditory-verbal STM performance in older adults.