Neural Processing of Health Information and Hypertension Self-Management in African Americans.

BACKGROUND: Uncontrolled blood pressure (BP) rates are persistently high among African Americans with hypertension. Although self-management is critical to controlling BP, little is known about the brain-behavior connections underlying the processing of health information and the performance of self-management activities. OBJECTIVES: In this pilot study, we explored the associations among neural processing of two types of health information and a set of self-management cognitive processes (self-efficacy, activation, decision-making, and hypertension knowledge) and behaviors (physical activity, dietary intake, and medication taking) and health status indicators (BP, health-related quality of life, anxiety, and depression). METHODS: Using a descriptive cross-sectional design, 16 African Americans with uncontrolled hypertension (mean age = 57.5 years, 68.8% women) underwent functional magnetic resonance imaging to assess activation of two neural networks, the task-positive network and the default mode network, and a region in the ventromedial prefrontal cortex associated with emotion-focused and analytic-focused health information. Participants completed self-reports and clinical assessments of self-management processes, behaviors, and health status indicators. RESULTS: Our hypothesis that neural processing associated with different types of health information would correlate with self-management cognitive processes and behaviors and health status indicators was only partially supported. Home diastolic BP was positively associated with ventromedial prefrontal cortex activation ( r = .536, p = .09); no other associations were found among the neural markers and self-management or health status variables. Expected relationships were found among the self-management processes and behaviors and health status indicators. DISCUSSION: To advance our understanding of the neural processes underlying health information processing and chronic illness self-management, future studies are needed that use larger samples with more heterogeneous populations and additional neuroimaging techniques.

Neural Processing and Perceived Discrimination Stress in African Americans.

BACKGROUND: Racial discrimination is one of many barriers experienced by African Americans that interfere with health self-care management. Discrimination stress may decrease the tendency for individuals to resonate with the social-emotional appeals embedded in persuasive health information, which are known to play a key role in producing behavior change. Understanding the neurobehavioral underpinnings of discrimination stress experienced by African Americans may help reduce or resolve this important health disparity. OBJECTIVES: The purpose of this secondary analysis was to examine the association between neural processing of health information and perceived discrimination. In particular, we focused on three previously identified measures of health information processing associated with distinct brain areas: analytic network, empathy network, and the ventral medial prefrontal cortex. METHODS: Data were obtained from 24 African Americans enrolled in a blood pressure self-care management study. Participants completed surveys assessing racial discrimination and global stress, as well as a 40-minute functional magnetic resonance imaging protocol used to measure neural activation associated with processing different types of health information. RESULTS: Discrimination stress was significantly related to reduced activation of the empathy network and ventral medial prefrontal cortex, whereas there was a nonsignificant positive relationship with activity in the analytic network. DISCUSSION: Uncovering associations between patient experiences, such as racial discrimination, and their neural processing of health information can lead to the development of tailored health messages and self-care management interventions. This may inform strategies to close the gap on health outcomes.

The relationships between health information behavior and neural processing in african americans with prehypertension.

Information behavior may enhance hypertension self-management in African-Americans. The goal of this substudy was to examine relationships between measures of self-reported health information behavior and neural measures of health information processing in a sample of 19 prehypertensive African-Americans (mean age=52.5, 52.6% women). We measured 1) health information seeking, sharing, and use (surveys) and 2) neural activity using functional magnetic resonance imaging (fMRI) to assess response to health information videos. We hypothesized that differential activation (comparison of analytic vs. empathic brain activity when watching a specific type of video) would indicate better function in three, distinct cognitive domains: 1) Analytic Network, 2) Default Mode Network (DMN), and 3) ventromedial prefrontal cortex (vmPFC). Scores on the information sharing measure (but not seeking or use) were positively associated with differential activation in the vmPFC (rs=.53, p=.02) and the DMN (rs=.43, p=.06). Our findings correspond with previous work indicating that activation of the DMN and vmPFC is associated with sharing information to persuade others, and with behavior change. Although health information is commonly conveyed as detached and analytic in nature, our findings suggest that neural processing of socially and emotionally salient health information is more closely associated with health information sharing.

The Effect of an HIV Self-Management Intervention on Neurocognitive Behavioral Processing.

People living with HIV (PLHIV) are increasingly diagnosed with comorbidities which require increasing self-management. We examined the effect of a self-management intervention on neurocognitive behavioral processing. Twenty-nine PLHIV completed a two-group, 3-month randomized clinical trial testing a self-management intervention to improve physical activity and dietary intake. At baseline and 3 months later, everyone completed validated assessments of physical, diet, and neurocognitive processing (functional magnetic resonance imaging [fMRI]-derived network analyses). We used linear mixed effects modeling with a random intercept to examine the effect of the intervention. The intervention improved healthy eating (p = .08) but did not improve other self-management behaviors. There was a significant effect of the intervention on several aspects of neurocognitive processing including in the task positive network (TPN) differentiation (p = .047) and an increase in the default mode network (DMN) differentiation (p = .10). Self-management interventions may influence neurocognitive processing in PLHIV, but those changes were not associated with positive changes in self-management behavior.

Characterization of Brain Signatures to Add Precision to Self-Management Health Information Interventions.

BACKGROUND: Although many of the proposed mediating processes of self-management interventions are operationally defined as cognitive processes (e.g., acquiring and using information, self-efficacy, motivation, and decision-making), little is known about their underlying brain mechanisms. Brain biomarkers of how people process health information may be an important characteristic on which to individualize health information to optimize self-management of chronic conditions. OBJECTIVES: We describe a program of research addressing the identification of brain biomarkers that differentially predict responses to two types of health information (analytic focused and emotion focused) designed to support optimal self-management of chronic conditions. METHODS: We pooled data from two pilot studies (N = 52) that included functional magnetic resonance imaging during a specially designed, ecologically valid protocol to examine brain activation (task differentiation) associated with two large-scale neural networks-the Analytic Network and the Empathy Network-and the ventral medial prefrontal cortex while individuals responded to different types of health information (analytic and emotional). RESULTS: Findings indicate that analytic information and emotional information are processed differently in the brain, and the magnitude of this differentiation in response to type of information varies from person to person. Activation in the a priori regions identified in response to both analytic and emotion information was confirmed. The feasibility of obtaining brain imaging data from persons with chronic conditions also is demonstrated. DISCUSSION: An understanding of brain signatures related to information processing has potential to assist in the design of more individualized, effective self-management interventions.

Dynamic adjustment of stimuli in real time functional magnetic resonance imaging.

The conventional fMRI image analysis approach to associating stimuli to brain activation is performed by carrying out a massive number of parallel univariate regression analyses. fMRI blood-oxygen-level dependent (BOLD) signal, the basis of these analyses, is known for its low signal-noise-ratio and high spatial and temporal signal correlation. In order to ensure accurate localization of brain activity, stimulus administration in an fMRI session is often lengthy and repetitive. Real-time fMRI BOLD signal analysis is carried out as the signal is observed. This method allows for dynamic, real-time adjustment of stimuli through sequential experimental designs. We have developed a voxel-wise sequential probability ratio test (SPRT) approach for dynamically determining localization, as well as decision rules for stopping stimulus administration. SPRT methods and general linear model (GLM) approaches are combined to identify brain regions that are activated by specific elements of stimuli. Stimulus administration is dynamically stopped when sufficient statistical evidence is collected to determine activation status across regions of interest, following predetermined statistical error thresholds. Simulation experiments and an example based on real fMRI data show that scan volumes can be substantially reduced when compared with pre-determined, fixed designs while achieving similar or better accuracy in detecting activated voxels. Moreover, the proposed approach is also able to accurately detect differentially activated areas, and other comparisons between task-related GLM parameters that can be formulated in a hypothesis-testing framework. Finally, we give a demonstration of SPRT being employed in conjunction with a halving algorithm to dynamically adjust stimuli.

Antagonistic neural networks underlying differentiated leadership roles.

The emergence of two distinct leadership roles, the task leader and the socio-emotional leader, has been documented in the leadership literature since the 1950s. Recent research in neuroscience suggests that the division between task-oriented and socio-emotional-oriented roles derives from a fundamental feature of our neurobiology: an antagonistic relationship between two large-scale cortical networks - the task-positive network (TPN) and the default mode network (DMN). Neural activity in TPN tends to inhibit activity in the DMN, and vice versa. The TPN is important for problem solving, focusing of attention, making decisions, and control of action. The DMN plays a central role in emotional self-awareness, social cognition, and ethical decision making. It is also strongly linked to creativity and openness to new ideas. Because activation of the TPN tends to suppress activity in the DMN, an over-emphasis on task-oriented leadership may prove deleterious to social and emotional aspects of leadership. Similarly, an overemphasis on the DMN would result in difficulty focusing attention, making decisions, and solving known problems. In this paper, we will review major streams of theory and research on leadership roles in the context of recent findings from neuroscience and psychology. We conclude by suggesting that emerging research challenges the assumption that role differentiation is both natural and necessary, in particular when openness to new ideas, people, emotions, and ethical concerns are important to success.

Rethinking the role of the rTPJ in attention and social cognition in light of the opposing domains hypothesis: findings from an ALE-based meta-analysis and resting-state functional connectivity.

The right temporo-parietal junction (rTPJ) has been associated with two apparently disparate functional roles: in attention and in social cognition. According to one account, the rTPJ initiates a "circuit-breaking" signal that interrupts ongoing attentional processes, effectively reorienting attention. It is argued this primary function of the rTPJ has been extended beyond attention, through a process of evolutionarily cooption, to play a role in social cognition. We propose an alternative account, according to which the capacity for social cognition depends on a network which is both distinct from and in tension with brain areas involved in focused attention and target detection: the default mode network (DMN). Theory characterizing the rTPJ based on the area's purported role in reorienting may be falsely guided by the co-occurrence of two distinct effects in contiguous regions: activation of the supramarginal gyrus (SMG), associated with its functional role in target detection; and the transient release, during spatial reorienting, of suppression of the angular gyrus (AG) associated with focused attention. Findings based on meta-analysis and resting functional connectivity are presented which support this alternative account. We find distinct regions, possessing anti-correlated patterns of resting connectivity, associated with social reasoning (AG) and target detection (SMG) at the rTPJ. The locus for reorienting was spatially intermediate between the AG and SMG and showed a pattern of connectivity with similarities to social reasoning and target detection seeds. These findings highlight a general methodological concern for brain imaging. Given evidence that certain tasks not only activate some areas but also suppress activity in other areas, it is suggested that researchers need to distinguish two distinct putative mechanisms, either of which may produce an increase in activity in a brain area: functional engagement in the task vs. release of suppression.

Visioning in the brain: an fMRI study of inspirational coaching and mentoring.

Effective coaching and mentoring is crucial to the success of individuals and organizations, yet relatively little is known about its neural underpinnings. Coaching and mentoring to the Positive Emotional Attractor (PEA) emphasizes compassion for the individual's hopes and dreams and has been shown to enhance a behavioral change. In contrast, coaching to the Negative Emotional Attractor (NEA), by focusing on externally defined criteria for success and the individual's weaknesses in relation to them, does not show sustained change. We used fMRI to measure BOLD responses associated with these two coaching styles. We hypothesized that PEA coaching would be associated with increased global visual processing and with engagement of the parasympathetic nervous system (PNS), while the NEA coaching would involve greater engagement of the sympathetic nervous system (SNS). Regions showing more activity in PEA conditions included the lateral occipital cortex, superior temporal cortex, medial parietal, subgenual cingulate, nucleus accumbens, and left lateral prefrontal cortex. We relate these activations to visioning, PNS activity, and positive affect. Regions showing more activity in NEA conditions included medial prefrontal regions and right lateral prefrontal cortex. We relate these activations to SNS activity, self-trait attribution and negative affect.

Seeing human: distinct and overlapping neural signatures associated with two forms of dehumanization.

The process of dehumanization, or thinking of others as less than human, is a phenomenon with significant societal implications. According to Haslam's (2006) model, two concepts of humanness derive from comparing humans with either animals or machines: individuals may be dehumanized by likening them to either animals or machines, or humanized by emphasizing differences from animals or machines. Recent work in cognitive neuroscience emphasizes understanding cognitive processes in terms of interactions between distributed cortical networks. It has been found that reasoning about internal mental states is associated with activation of the default mode network (DMN) and deactivation of the task positive network (TPN); whereas reasoning about mechanical processes produces the opposite pattern. We conducted two neuroimaging studies. The first examined the neural bases of dehumanization and its relation to these two brain networks, using images and voice-over social narratives which either implicitly contrasted or implicitly likened humans to either animals or machines. The second study addressed a discrepancy between findings from the first study and prior work on the neural correlates of dehumanization: using a design similar to prior work we examined neural responses to pictures of humans, animals and machines, presented without any social context. In both studies, human and humanizing conditions were associated with relatively high activity in the DMN and relatively low activity in the TPN. However, the non-human and dehumanizing conditions deviated in different ways: they demonstrated more marked changes either in the DMN or in the TPN. Notably, differences between the animal dehumanizing and humanizing conditions were most evident in regions associated with mechanistic reasoning, not in the mentalizing network. Conjunction analysis of contrasts from both paradigms revealed that only one region was consistently more active when participants saw human, a medial parietal region regarded as the central hub of the DMN. These findings provide a neural basis for Haslam's distinction between two types of dehumanization, and suggest that the DMN and TPN play opposing roles in creating a sense of moral concern.

fMRI reveals reciprocal inhibition between social and physical cognitive domains.

Two lines of evidence indicate that there exists a reciprocal inhibitory relationship between opposed brain networks. First, most attention-demanding cognitive tasks activate a stereotypical set of brain areas, known as the task-positive network and simultaneously deactivate a different set of brain regions, commonly referred to as the task negative or default mode network. Second, functional connectivity analyses show that these same opposed networks are anti-correlated in the resting state. We hypothesize that these reciprocally inhibitory effects reflect two incompatible cognitive modes, each of which may be directed towards understanding the external world. Thus, engaging one mode activates one set of regions and suppresses activity in the other. We test this hypothesis by identifying two types of problem-solving task which, on the basis of prior work, have been consistently associated with the task positive and task negative regions: tasks requiring social cognition, i.e., reasoning about the mental states of other persons, and tasks requiring physical cognition, i.e., reasoning about the causal/mechanical properties of inanimate objects. Social and mechanical reasoning tasks were presented to neurologically normal participants during fMRI. Each task type was presented using both text and video clips. Regardless of presentation modality, we observed clear evidence of reciprocal suppression: social tasks deactivated regions associated with mechanical reasoning and mechanical tasks deactivated regions associated with social reasoning. These findings are not explained by self-referential processes, task engagement, mental simulation, mental time travel or external vs. internal attention, all factors previously hypothesized to explain default mode network activity. Analyses of resting state data revealed a close match between the regions our tasks identified as reciprocally inhibitory and regions of maximal anti-correlation in the resting state. These results indicate the reciprocal inhibition is not attributable to constraints inherent in the tasks, but is neural in origin. Hence, there is a physiological constraint on our ability to simultaneously engage two distinct cognitive modes. Further work is needed to more precisely characterize these opposing cognitive domains.

Anticipatory and stimulus-evoked blood oxygenation level-dependent modulations related to spatial attention reflect a common additive signal.

Covert attention is associated with prestimulus blood oxygenation level-dependent (BOLD) modulations in visual cortex. In some situations, this preparatory activity can predict how well human subjects will perceive upcoming visual objects. Preparatory activity may mediate this behavioral effect by affecting the stimulus-evoked response, but the relationship between preparatory and stimulus-evoked BOLD modulations is unclear. Here, we examine this relationship by comparing the effects of spatial attention on anticipatory and stimulus-evoked signals and by measuring the trial-to-trial correlation between prestimulus and poststimulus modulations. We find that in extrastriate visual cortex (V4), modulations related to spatial attention are relatively large, extend from prestimulus through the peak of the evoked response, and are slightly larger in the evoked response compared with the prestimulus response. In striate cortex (V1), the frontal eye fields (FEF), and the intraparietal sulcus (IPS), modulations related to spatial attention are relatively small, are confined primarily to the prestimulus period, and are slightly larger in preparatory versus stimulus-evoked activity. Importantly, across visual cortex, the attentional biases (activity for attended versus unattended locations) in preparatory and evoked activity are more positively correlated, trial-by-trial, than would be expected on the basis of activity measured in subjects at rest. We argue that this pattern of results suggests that the same mechanisms underlie preparatory and stimulus-evoked BOLD modulations related to spatial attention and that incoming sensory signals add to preexistent biases in preparatory activity to generate the stimulus-evoked response.

Anticipatory suppression of nonattended locations in visual cortex marks target location and predicts perception.

Spatial attention is associated with modulations in prestimulus, anticipatory blood oxygen level-dependent (BOLD) activity across the brain. It is unclear, however, if these anticipatory modulations depend on the computational demands of the upcoming task. Here, we show that anticipation of low-contrast stimuli, relative to high-contrast stimuli, is associated with increased prestimulus BOLD activity in the frontal eye field (FEF) and the posterior inferior frontal sulcus (IFS) but not in the intraparietal sulcus (IPS). In visual cortex, anticipation of low-contrast stimuli is associated with increased suppression of activity corresponding to unattended (but not attended) locations, and this suppression predicts whether subjects will accurately perceive low-contrast stimuli. These results suggest that when a stimulus will be difficult to distinguish from the background, top-down signals from FEF and IFS can facilitate perception by marking its location through the suppression of unattended locations in visual cortex.

Asymmetry of anticipatory activity in visual cortex predicts the locus of attention and perception.

Humans can use advance information to direct spatial attention before stimulus presentation and respond more accurately to stimuli at the attended location compared with unattended locations. Likewise, spatially directed attention is associated with anticipatory activity in the portion of visual cortex representing the attended location. It is unknown, however, whether and how anticipatory signals predict the locus of spatial attention and perception. Here, we show that prestimulus, preparatory activity is highly correlated across regions representing attended and unattended locations. Comparing activity representing attended versus unattended locations, rather than measuring activity for only one location, dramatically improves the accuracy with which preparatory signals predict the locus of attention, largely by removing this positive correlation common across locations. In V3A, moreover, only the difference in activity between attended and unattended locations predicts whether upcoming visual stimuli will be accurately perceived. These results suggest that the locus of attention is coded in visual cortex by an asymmetry of anticipatory activity between attended and unattended locations and that this asymmetry predicts the accuracy of perception. This coding strategy may bias activity in downstream brain regions to represent the stimulus at the attended location.

Changing human visual field organization from early visual to extra-occipital cortex.

BACKGROUND: The early visual areas have a clear topographic organization, such that adjacent parts of the cortical surface represent distinct yet adjacent parts of the contralateral visual field. We examined whether cortical regions outside occipital cortex show a similar organization. METHODOLOGY/PRINCIPAL FINDINGS: The BOLD responses to discrete visual field locations that varied in both polar angle and eccentricity were measured using two different tasks. As described previously, numerous occipital regions are both selective for the contralateral visual field and show topographic organization within that field. Extra-occipital regions are also selective for the contralateral visual field, but possess little (or no) topographic organization. A regional analysis demonstrates that this weak topography is not due to increased receptive field size in extra-occipital areas. CONCLUSIONS/SIGNIFICANCE: A number of extra-occipital areas are identified that are sensitive to visual field location. Neurons in these areas corresponding to different locations in the contralateral visual field do not demonstrate any regular or robust topographic organization, but appear instead to be intermixed on the cortical surface. This suggests a shift from processing that is predominately local in visual space, in occipital areas, to global, in extra-occipital areas. Global processing fits with a role for these extra-occipital areas in selecting a spatial locus for attention and/or eye-movements.

Separate modulations of human V1 associated with spatial attention and task structure.

Functional magnetic resonance imaging (fMRI) was used while normal human volunteers engaged in simple detection and discrimination tasks, revealing separable modulations of early visual cortex associated with spatial attention and task structure. Both modulations occur even when there is no change in sensory stimulation. The modulation due to spatial attention is present throughout the early visual areas V1, V2, V3, and VP, and varies with the attended location. The task structure activations are strongest in V1 and are greater in regions that represent more peripheral parts of the visual field. Control experiments demonstrate that the task structure activations cannot be attributed to visual, auditory, or somatosensory processing, the motor response for the detection/discrimination judgment, or oculomotor responses such as blinks or saccades. These findings demonstrate that early visual areas are modulated by at least two types of endogenous signals, each with distinct cortical distributions.

Imaging the intentional stance in a competitive game.

The "intentional stance" is the disposition to treat an entity as a rational agent, possessing particular beliefs, desires, and intentions, in order to interpret and predict it's behavior. The intentional stance is a component of a broader social cognitive function, mentalizing. Here we report a study that investigates the neural substrates of "on-line" mentalizing, using PET, by asking volunteers to second-guess an opponent. In order to identify brain activity specifically associated with adoption of an intentional stance, we used a paradigm that allowed tight control of other cognitive demands. Volunteers played a computerised version of the children's game "stone, paper, scissors." In the mentalizing condition volunteers believed they were playing against the experimenter. In the comparison condition, volunteers believed they were playing against a computer. In fact, during the actual scanning, the "opponent" produced a random sequence in both conditions. The only difference was the attitude, or stance, adopted by the volunteer. Only one region was more active when volunteers adopted the intentional stance. This was in anterior paracingulate cortex (bilaterally). This region has been activated in a number of previous studies involving mentalizing. However, this is the first study suggesting a specific link between activity in this brain region and the adoption of an intentional stance.