Michael E. Silverman

Effect of Attention Therapy on Reading Comprehension

This study quantified the influence of visual attention therapy on the reading comprehension of Grade 6 children with moderate reading disabilities (RD) in the absence of specific reading remediation. Thirty students with below-average reading scores were identified using standardized reading comprehension tests. Fifteen children were placed randomly in the experimental group and 15 in the control group. The Attention Battery of the Cognitive Assessment System was administered to all participants. The experimental group received 12 one-hour sessions of individually monitored, computer-based attention therapy programs; the control group received no therapy during their 12-week period. Each group was retested on attention and reading comprehension measures. In order to stimulate selective and sustained visual attention, the vision therapy stressed various aspects of arousal, activation, and vigilance. At the completion of attention therapy, the mean standard attention and reading comprehension scores of the experimental group had improved significantly. The control group, however, showed no significant improvement in reading comprehension scores after 12 weeks. Although uncertainties still exist, this investigation supports the notion that visual attention is malleable and that attention therapy has a significant effect on reading comprehension in this often neglected population.

Neural Dysfunction in Postpartum Depression: An fMRI Pilot Study

INTRODUCTION With approximately 4 million births each year in the United States, an estimated 760,000 women annually suffer from a clinically significant postpartum depressive illness. Yet even though the relationship between psychiatric disorders and the postpartum period has been documented since the time of Hippocrates, fewer than half of all these cases are recognized. OBJECTIVE Because postpartum depression (PPD), the most common complication of childbearing, remains poorly characterized, and its etiology remains unclear, we attempted to address a critical gap in the mechanistic understanding of PPD by probing its systems-level neuropathophysiology, in the context of a specific neurobiological model of fronto-limbic-striatal function. METHODS Using emotionally valenced word probes, with linguistic semantic specificity within an integrated functional magnetic resonance imaging (fMRI) protocol, we investigated emotional processing, behavioral regulation, and their interaction (functions of clinical relevance to PPD), in the context of fronto-limbic-striatal function. RESULTS We observed attenuated activity in posterior orbitofrontal cortex for negative versus neutral stimuli with greater PPD symptomatology, increased amygdala activity in response to negative words in those without PPD symptomotology, and attenuated striatum activation to positive word conditions with greater PPD symptomotology. CONCLUSION Identifying the functional neuroanatomical profile of brain systems involved in the regulation of emotion and behavior in the postpartum period will not only assist in determining whether the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition psychiatric diagnostic specifier of PPD has an associated, unique, functional neuroanatomical profile, but a neurobiological characterization in relation to asymptomatic (postpartum non-depressed) control subjects, will also increase our understanding of the affective disorder spectrum, shed additional light on the possible mechanism(s) responsible for PPD and provide a necessary foundation for the development of more targeted, biologically based diagnostic and therapeutic strategies for PPD.

Role of Visual Attention in Cognitive Control of Oculomotor Readiness in Students with Reading Disabilities

This study investigated eye movement and comprehension therapy in Grade 6 children with reading disabilities (RD). Both order of therapy and type of therapy were examined. Furthermore, the implications of visual attention in ameliorating reading disability are discussed. Thirty-one students with RD were identified using standardized reading comprehension tests. Eye movements were analyzed objectively using an infra-red recording device. Reading scores of participating children were 0.5 to 1 SD below the national mean. Testing took place before the start of therapy (T1) and was repeated after 12 weeks (T2) and 24 weeks (T3) of therapy. One group of students had eye movement therapy first, followed by comprehension therapy; in the other group, the order was reversed. Data were evaluated using a repeated measures MANOVA and post hoc tests. At T1, mean reading grade was 2 years below grade level, and eye movement scores were at about Grade 2 level. Mean growth in reading comprehension for the total sample was 2.6 years (p < .01) at T3; equally significant improvement was measured in eye movements (p < .01). Learning rate in reading comprehension improved from 60% (T1) to 400% (T3). Although within-group differences were statistically significant, between-group differences were not significant for comprehension or eye movements. Order of therapy (comprehension first or eye movements first) was not significant. Improvements in within-group scores for comprehension and eye movements were consistently significant at T2 and T3. Eye movement therapy improved eye movements and also resulted in significant gains in reading comprehension. Comprehension therapy likewise produced improvement both in eye movement efficiency and in reading comprehension. The results support the notion of a cognitive link among visual attention, oculomotor readiness, and reading comprehension.

Change blindness and priming: When it does and does not occur

In a series of three experiments, we explored the nature of implicit representations in change blindness (CB). Using 3 x 3 letter arrays, we asked subjects (Ss) to locate changes in paired arrays separated by 80 ms ISIs, in which one, two or three letters of a row in the second array changed. In one testing version, a tone followed the second array, signaling a row for partial report (PR). In the other version, no PR was required. After Ss reported whether a change had been detected and the PR had been completed (if required), they were asked to identify a degraded letter trigram that was either novel, or from a previously shown row (repetition priming). Our findings indicate that when CB occurs, both the pre-change and post-change stimulus information primes despite its unavailability to consciousness. Surprisingly, findings also indicate that when change detection occurs only the post-change information primes.

Frontolimbic function and cortisol reactivity in response to emotional stimuli

Frontolimbic structures involved in fear conditioning have also been associated with hypothalamic–pituitary–adrenal (HPA)-axis modulation, including amygdaloid, hippocampal, and ventromedial prefrontal cortex regions. Although HPA-axis function and endocrine changes have been investigated in the context of stress provocation, much research has not been conducted using functional neuroimaging in the study of the HPA axis and frontolimbic function in response to emotional stimuli. Using functional magnetic resonance imaging, the association of blood-oxygen-level dependent signal with salivary cortisol in response to an emotional visual scene paradigm was investigated, with prescan and postscan salivary cortisol analyzed as a covariate of interest during specific conditions. Cortisol reactivity to the paradigm was positively associated with amygdalar and hippocampal activity and negatively associated with ventromedial prefrontal cortex activity in conditions involving emotional imagery.

The neural processing of negative emotion postpartum: a preliminary study of amygdala function in postpartum depression

While contemporary diagnostic nosology characterizes postpartum depression (PPD) as a specifier of a major depressive disorder (MDD), this classification continues to be questioned. Functional magnetic resonance imaging (fMRI) holds the promise of helping to characterize the neuroanatomical dysfunction associated with dysregulated emotion after childbirth. Twenty postpartum women underwent fMRI in the presence of emotionally valenced stimuli. The observation of relative amygdala non-responsivity in subjects demonstrating greater depression symptomotology stands in contrast to imaging studies of MDD and provides insight into possible phenotypic differences of PPD.

The risk factors for postpartum depression: A population‐based study

Postpartum depression (PPD) can result in negative personal and child developmental outcomes. Only a few large population‐based studies of PPD have used clinical diagnoses of depression and no study has examined how a maternal depression history interacts with known risk factors. The objective of this study was to examine the impact of a depression history on PPD and pre‐ and perinatal risk factors.

The Impact of Socioeconomic Status on the Neural Substrates Associated with Pleasure

Low socio-economic status (SES) is associated with increased morbidity and premature mortality. Because tonic adversity relates to a diminished ability to experience pleasure, we hypothesized that subjects living in poverty would show diminished neural responsivity to positive stimuli in regions associated with positive experience and reward. Visual images were presented to twenty-two subjects in the context of a EPI-BOLD fMRI paradigm. Significant differences in neural responses between SES groups to poverty vs. neutral images were assessed, examining group, condition, and interaction effects. The data suggest that persons living in low-SES have neural experiences consistent with diminished interest in things generally enjoyed and point toward a possible explanation for the relationship between socioeconomic inequalities and mood disorders, such as depression, by SES.

Posterior cortical atrophy: an exemplar for renovating diagnostic formulation in neuropsychiatry.

Neurodegenerative dementias represent among the most clinically and pathologically complex syndromes in neuropsychiatry. Phenomenologically protean, and often initially presenting with subtle subsyndromal characteristics, neurodegenerative behavioral syndromes can manifest with an assortment of cognitive, mood, personality, and comportmental changes, often alloyed with elementary neurologic (e.g., motor) signs. A range of pathogenic mechanisms (e.g., amyloid plaques, Pick bodies, etc) typically underlie corresponding clinical syndromes. However, overlap in both clinical expression and histopathologic comorbidities frequently exist among cortical and subcortical neurodegenerative disorders. Moreover, secondary central nervous system pathologies (e.g., cerebrovascular disease) commonly coexist with neurodegenerative processes, further complicating clinical phenomenology-based nosologic categorization. Evolving insight into the etiologic mechanisms of neurodegenerative dementias, and correspondingly improving potential for intervention, require more precise differentiation among dementia subtypes and comprehensive identification of contemporaneous neurodegenerative processes. Increasing appreciation of this diagnostic complexity is prompting the need for renovation of existing diagnostic schemas. We address these issues by reviewing the atypical dementia type known as posterior cortical atrophy. We then use posterior cortical atrophy as an exemplar for renovating neuropsychiatric diagnostic classification to better account for the layered complexity of clinical and pathologic domains needing to be characterized to accurately and completely diagnose neuropsychiatric disturbances.

Autonomics and cognition

The neural mechanisms of cognition represent one of the most exciting frontiers of contemporary neuroscience [1, 2]. Theoretical and methodological innovations, enabling paradigmatic advances in probing cognitive functions, are driving progress in the exploration of their mechanisms. A key component of these advances involves integration of autonomic neurophysiologic measures into neural studies of cognition, the focus of the article ‘‘Cognitive functioning in orthostatic hypotension due to pure autonomic failure’’ by Heims and colleagues appearing in this issue of Clinical Autonomic Research. A basic challenge of cognitive neuroscience’s quest to elucidate neural mechanisms of cognition involves accurately characterizing that cognition to which a neural substrate is related. Since even standardized stimuli can yield variable cognitive responses, and subjective reports of thought processes are insufficient [3], investigators need ways to empirically confirm that a subject is mentating in the way they think a subject is mentating. In order to legitimately associate specific mentation with a specific neural mechanism, investigators have turned to autonomic measures. The scientific importance of integrating autonomic assays into behavioral studies is demonstrated by evidence revealing (a) an integral role of autonomic processes in cognition, and (b) that peripheral autonomic assays can be used as indices of mental functions. Consequently, autonomic assays are an increasingly recognized requirement for neural studies of cognition, and are being joined with functional neuroimaging and novel neuropsychological activation paradigms to elucidate heretofore obscure mechanisms of cognition. Indeed, autonomic neurology is emerging as a key nexus of cognitive neuroscience, behavioral neurology, and neuropsychiatry. The work by Heims et al. employs theory and methodology at the core of this coalescence. To put the article’s focus into context within current cognitive and autonomic neuroscience, and the authors’ strategic employment of the disease model pure autonomic failure (PAF), we briefly review the development of this nexus.