The primary taste cortex consists of the insula and operculum. Previous work has indicated that neurons in the primary taste cortex respond solely to sensory input from taste receptors and lingual somatosensory receptors. Using functional magnetic resonance imaging, we show here that expectancy modulates these neural responses in humans. When subjects were led to believe that a highly aversive bitter taste would be less distasteful than it actually was, they reported it to be less aversive than when they had accurate information about the taste and, moreover, the primary taste cortex was less strongly activated. In addition, the activation of the right insula and operculum tracked online ratings of the aversiveness for each taste. Such expectancy-driven modulation of primary sensory cortex may affect perceptions of external events.
Zotero Collections:
Although the co-occurrence of negative affect and pain is well recognized, the mechanism underlying their association is unclear. To examine whether a common self-regulatory ability impacts the experience of both emotion and pain, we integrated neuroimaging, behavioral, and physiological measures obtained from three assessments separated by substantial temporal intervals. Our results demonstrated that individual differences in emotion regulation ability, as indexed by an objective measure of emotional state, corrugator electromyography, predicted self-reported success while regulating pain. In both emotion and pain paradigms, the amygdala reflected regulatory success. Notably, we found that greater emotion regulation success was associated with greater change of amygdalar activity following pain regulation. Furthermore, individual differences in degree of amygdalar change following emotion regulation were a strong predictor of pain regulation success, as well as of the degree of amygdalar engagement following pain regulation. These findings suggest that common individual differences in emotion and pain regulatory success are reflected in a neural structure known to contribute to appraisal processes.
Zotero Collections:
The amygdalae are important, if not critical, brain regions for many affective, attentional and memorial processes, and dysfunction of the amygdalae has been a consistent finding in the study of clinical depression. Theoretical models of the functional neuroanatomy of both normal and psychopathological affective processes which posit cortical hemispheric specialization of functions have been supported by both lesion and functional neuroimaging studies in humans. Results from human neuroimaging studies in support of amygdalar hemispheric specialization are inconsistent. However, recent results from human lesion studies are consistent with hemispheric specialization. An important, yet largely ignored, feature of the amygdalae in the primate brain--derived from both neuroanatomical and electrophysiological data--is that there are virtually no direct interhemispheric connections via the anterior commissure (AC). This feature stands in stark contrast to that of the rodent brain wherein virtually all amygdalar nuclei have direct interhemispheric connections. We propose this feature of the primate brain, in particular the human brain, is a result of influences from frontocortical hemispheric specialization which have developed over the course of primate brain evolution. Results consistent with this notion were obtained by examining the nature of human amygdalar interhemispheric connectivity using both functional magnetic resonance imaging (FMRI) and positron emission tomography (PET). We found modest evidence of amygdalar interhemispheric functional connectivity in the non-depressed brain, whereas there was strong evidence of functional connectivity in the depressed brain. We interpret and discuss the nature of this connectivity in the depressed brain in the context of dysfunctional frontocortical-amygdalar interactions which accompany clinical depression.
Zotero Collections:
On the basis of a review of the extant literature describing emotion-cognition interactions, the authors propose 4 methodological desiderata for studying how task-irrelevant affect modulates cognition and present data from an experiment satisfying them. Consistent with accounts of the hemispheric asymmetries characterizing withdrawal-related negative affect and visuospatial working memory (WM) in prefrontal and parietal cortices, threat-induced anxiety selectively disrupted accuracy of spatial but not verbal WM performance. Furthermore, individual differences in physiological measures of anxiety statistically mediated the degree of disruption. A second experiment revealed that individuals characterized by high levels of behavioral inhibition exhibited more intense anxiety and relatively worse spatial WM performance in the absence of threat, solidifying the authors' inference that anxiety causally mediates disruption. These observations suggest a revision of extant models of how anxiety sculpts cognition and underscore the utility of the desiderata.
Zotero Collections:
Zotero Collections:
<p>"Informed by the maxim that you can't study what you can't see, Baer's book provedes the necessary psychometric underpinning to further our understanding of core change processes in mindfulness-based interventions."---Zindel V. Segal, Ph.D., author of The Mindful Way Through Depression"This kind of attention to the reasons why mindfulness-based intervention may be beneficial will help stimulate informative research in the area and also help clinicians provide therapy that enhances these important skills."---Lizabeth Roemer, Ph.D., coauthor of Mindfulness-and Acceptance-Based Behavioral Therapies in Practice"An excellent resource not only for mindfulness researchers and practitioners, but for amyone interested in what leads to mental health and emotional balance."---Cassandra Vieten, Ph.D., director of research at the Institute of Noetic Sciences and author of Mindful Motherhood"A fascinating journey to the heart of what actually changes in mindfulness and acceptance-based treatment...Highly recommneded for psychotherapists, health care professionals, and anyone seeking the very latest scientific understanding of psychological change."---Christopher K. Germer, Ph.D., author of The Mindful Path to Self-CompassionHow does mindfulness work? Thousands of therapists utilize mindfulness-based treatments and have witnesed firsthand the effectiveness of these approaches on clients suffering from anxiety, depression, and other common mental health issues. But for many clinicians, the psychological processes and brain functions that explain these changes remain a mystery, and effective methodologies for measuring each client's progress are elusive.In Assessing Mindfulness and Acceptance Processes in Clients, Ruth Baer presents a collection of articles by some of the most respected mindfulness researchers and therapists practicing today. Each contribution assesses the variables that represent potential processes of change, such as mindfulness.acceptance, self-compassion, spirituality, and focus on values, and determines the importance of each of these processes to enhanced psychological functioning and quality of life. Clinicians learn to accurately measure each process in individual clients, an invaluable skill for any practicing therapist. A seminal contribution to the existing professional literature on mindfulnessbased treatments, this book is also an essential resource for any mental health professional seeking to illuminate the processes at work behind any mindfulness and acceptance-based therapy.</p>
Zotero Collections:
This study compared the asymmetry of different features of brain electrical activity during the performance of a verbal task (word finding) and a spatial task (dot localization) that had been carefully matched on psychometric properties and accompanying motor activity. Nineteen right-handed subjects were tested. EEG was recorded from F3, F4, C3, C4, P3, and P4, referred to both CZ and computer-derived averaged-ears references, and Fourier transformed. Power in the delta, theta, alpha, and beta bands was computed. There were significant Task X Hemisphere effects in all bands for CZ-referenced data and for the alpha and beta bands for ears-referenced data. The effects were always either greater power suppression in the hemisphere putatively most engaged in task processing or greater power in the opposite hemisphere. Correlations between EEG and task performance indicated that CZ-referenced parietal alpha asymmetry accounted for the most variance in verbal task performance. Power within individual hemispheres or across hemispheres was unrelated to task performance. The findings indicate robust differences in asymmetrical brain physiology that are produced by well-matched verbal and spatial cognitive tasks.
Zotero Collections:
Thirty-two participants were tested for both resting electroencephalography (EEG) and neuropsychological function. Eight one-minute trials of resting EEG were recorded from 14 channels referenced to linked ears, which was rederived to an average reference. Neuropsychological tasks included Verbal Fluency, the Tower of London, and Corsi's Recurring Blocks. Asymmetries in EEG alpha activity were correlated with performance on these tasks. Similar patterns were obtained for delta and theta bands. Factor analyses of resting EEG asymmetries over particular regions suggested that asymmetries over anterior scalp regions may be partly independent from those over posterior scalp regions. These results support the notions that resting EEG asymmetries are specified by multiple mechanisms along the rostral/caudal plane, and that these asymmetries predict task performance in a manner consistent with lesion and neuroimaging studies.
Zotero Collections:
<p>Drawing its main source of inspiration from a naturalized interpretation of Husserlian phenomenology, On Becoming Aware: A Pragmatics of Experiencing attempts to examine closely the nature of experience and how we may become aware of our own mental life. The authors also focus on how this project fits into the larger context of cognitive science, psychology, neurosciences, and philosophy. Additional partners in the effort to better understand experience are the contemplative systems of the world's spiritual or wisdom traditions, including particularly that of Buddhism. The book includes three separate glossaries of technical terms in phenomenology, the cognitive sciences, and Tibetan Buddhism. The book On Becoming Aware seeks a disciplined and practical approach to exploring human experience. While much of the book draws its inspiration from the phenomenological theories of Husserl, other approaches to the direct study of experience are also explored in depth. One of these approaches is embodied by the world's spiritual or wisdom or contemplative traditions such as Sufism, Buddhism, the Philokalia tradition, and others. Collectively, these traditions have come upon a variety of their own insights and methods for understanding experience, or, to use words from the phenomenological tradition, has developed its own ways of phenomenological reduction Amongst the various wisdom traditions, the authors focus mainly on Buddhism. The authors give an introduction to Buddhist theory and history, followed by an in-depth discussion of the Buddhist contemplative practices of mindfulness, śamatha, vipaśyanā, tonglen (gtong len), lojong (blo sbyong), dzokchen (rdzogs chen), and mahāmudrā. The authors then relate this discussion to themes from philosophy and phenomenology explored earlier in the book, paricularly Husserl's concept of épochè. (Zach Rowinski 2005-01-17) Publisher's description: This book searches for the sources and means for a disciplined practical approach to exploring human experience. The spirit of this book is pragmatic and relies on a Husserlian phenomenology primarily understood as a method of exploring our experience. The authors do not aim at a neo-Kantian a priori ‘new theory’ of experience but instead they describe a concrete activity: how we examine what we live through, how we become aware of our own mental life. The range of experiences of which we can become aware is vast: all the normal dimensions of human life (perception, motion, memory, imagination, speech, everyday social interactions), cognitive events that can be precisely defined as tasks in laboratory experiments (e.g., a protocol for visual attention), but also manifestations of mental life more fraught with meaning (dreaming, intense emotions, social tensions, altered states of consciousness). The central assertion in this work is that this immanent ability is habitually ignored or at best practiced unsystematically, that is to say, blindly. Exploring human experience amounts to developing and cultivating this basic ability through specific training. Only a hands-on, non-dogmatic approach can lead to progress, and that is what animates this book.</p>
Zotero Collections:
- Contexts of Contemplation Project,
- Buddhist Contemplation by Applied Subject,
- Contemplation by Applied Subject,
- Contemplation by Tradition,
- Philosophy and Contemplation,
- Philosophy and Buddhist Contemplation,
- Psychology and Buddhist Contemplation,
- Science and Buddhist Contemplation,
- Psychology and Contemplation,
- Science and Contemplation,
- Buddhist Contemplation
BACKGROUND: Studies using electroencephalogram (EEG) measures of activation asymmetry have reported differences in anterior asymmetry between depressed and nondepressed subjects. Several studies have suggested reciprocal relations between measures of anterior and posterior activation asymmetries. We hypothesized that depressed subjects would fail to show the normal activation of posterior right hemisphere regions in response to an appropriate cognitive challenge.
METHODS: EEG activity was recorded from 11 depressed and 19 nondepressed subjects during the performance of psychometrically matched verbal (word finding) and spatial (dot localization) tasks. Band power was extracted from all epochs of artifact-free data and averaged within each condition. Task performance was also assessed.
RESULTS: Depressed subjects showed a specific deficit in the performance of the spatial task, whereas no group differences were evident on verbal performance. In posterior scalp regions, nondepressed controls had a pattern of relative left-sided activation during the verbal task and relative right-sided activation during the spatial task. In contrast, depressed subjects failed to show activation in posterior right hemisphere regions during spatial task performance.
CONCLUSIONS: These findings suggest that deficits in right posterior functioning underlie the observed impairments in spatial functioning among depressed subjects.
Zotero Collections:
Biological systems are particularly prone to variation, and the authors argue that such variation must be regarded as important data in its own right. The authors describe a method in which individual differences are studied within the framework of a general theory of the population as a whole and illustrate how this method can be used to address three types of issues: the nature of the mechanisms that give rise to a specific ability, such as mental imagery; the role of psychological or biological mediators of environmental challenges, such as the biological bases for differences in dispositional mood; and the existence of processes that have nonadditive effects with behavioral and physiological variables, such as factors that modulate the response to stress and its effects on the immune response.
Zotero Collections:
The anterior medial prefrontal (AMPFC) and retrosplenial (RSC) cortices are active during self-referential decision-making tasks such as when participants appraise traits and abilities, or current affect. Other appraisal tasks requiring an evaluative decision or mental representation, such as theory of mind and perspective-taking tasks, also involve these regions. In many instances, these types of decisions involve a subjective opinion or preference, but also a degree of ambiguity in the decision, rather than a strictly veridical response. However, this ambiguity is generally not controlled for in studies that examine self-referential decision-making. In this functional magnetic resonance imaging experiment with 17 healthy adults, we examined neural processes associated with subjective decision-making with and without an overt self-referential component. The task required subjective decisions about colors-regarding self-preference (internal subjective decision) or color similarity (external subjective decision) under conditions where there was no objectively correct response. Results indicated greater activation in the AMPFC, RSC, and caudate nucleus during internal subjective decision-making. The findings suggest that self-referential processing, rather than subjective judgments among ambiguous response alternatives, accounted for the AMPFC and RSC response.
Zotero Collections:
The article discusses the psychological notion of mindfulness, which denotes focusing on the present and ignoring unhelpful thoughts, in relation to Christian beliefs. It notes the Buddhist origins of the term in the context of meditation, the relation between mindfulness and the self, and the use of Focused Breathing Awareness (FBA) techniques.
Zotero Collections:
- Contexts of Contemplation Project,
- Buddhist Contemplation by Applied Subject,
- Contemplation by Applied Subject,
- Contemplation by Tradition,
- Psychology and Buddhist Contemplation,
- Science and Buddhist Contemplation,
- Interreligious Contemplation,
- Psychology and Contemplation,
- Science and Contemplation,
- Christian Contemplation,
- Buddhist Contemplation
We propose that cognition is more than a collection of independent processes operating in a modular cognitive system. Instead, we propose that cognition emerges from dependencies between all of the basic systems in the brain, including goal management, perception, action, memory, reward, affect, and learning. Furthermore, human cognition reflects its social evolution and context, as well as contributions from a developmental process. After presenting these themes, we illustrate their application to the process of anticipation. Specifically, we propose that anticipations occur extensively across domains (i.e., goal management, perception, action, reward, affect, and learning) in coordinated manners. We also propose that anticipation is central to situated action and to social interaction, and that many of its key features reflect the process of development.
Zotero Collections:
<p>This study investigated the effects of imagery on flexibility and the relations among verbal and non-verbal and spontaneous and adaptive flexibility measures. Finally, the effects of brain damage on flexibility and imagery were investigated. Historical and more recent concepts of the cognitive rigidity flexibility dimension were discussed with special emphasis on the effects of brain damage. Forty female and fourteen male volunteer students were tested with verbal and non-verbal flexibility tests. Measures of spontaneous flexibility were the Word Fluency Test and the Five Point Test and measures of adaptive flexibility were the Stroop Test and a newly introduced concept identification test, assessing imagery and interference concepts. Furthermore, a questionnaire to assess individual imagery styles was employed as well as the vocabulary and block design subtests of the WAIS. The results of brain damaged subjects were compared to a matched control group. Furthermore, z-score profiles were prepared to compare the test patterns between the different patient groups. Four dimensions of cognitive flexibility-rigidity were found in healthy subjects. Furthermore it was found that individual imagery styles had little influence on the performance in flexibility tests. A trend was showing that "habitual verbalizers" had no advantage in solving the tests and had in fact more difficulty with the identification of non-verbal concepts. No significant gender effects were found. Brain damaged patients performed significantly more poorly than normal subjects in all flexibility tests. Several test- and subject variables that effect the performance on flexibility tests were discussed. It was concluded that rigidity-flexibility measures represent different dimensions depending on stimulus mode and type of task. It was further concluded that behavioral rigidity-flexibility is not only the function of test variables, but also of various subject variables namely imagery style, intelligence, age, gender and brain damage. In healthy people, the performance on one test was not found to be predictive for the performance on another flexibility test. On the other hand, in brain damaged subjects rigid behavior seems to extend to a wider range of test performance. Finally, different performance patterns were described for different lesion sites in brain damaged.</p>
Zotero Collections:
Functional neuroimaging research has demonstrated that retrieving information about object-associated colors activates the left fusiform gyrus in posterior temporal cortex. Although regions near the fusiform have previously been implicated in color perception, it remains unclear whether color knowledge retrieval actually activates the color perception system. Evidence to this effect would be particularly strong if color perception cortex was activated by color knowledge retrieval triggered strictly with linguistic stimuli. To address this question, subjects performed two tasks while undergoing fMRI. First, subjects performed a property verification task using only words to assess conceptual knowledge. On each trial, subjects verified whether a named color or motor property was true of a named object (e.g., TAXI-yellow, HAIR-combed). Next, subjects performed a color perception task. A region of the left fusiform gyrus that was highly responsive during color perception also showed greater activity for retrieving color than motor property knowledge. These data provide the first evidence for a direct overlap in the neural bases of color perception and stored information about object-associated color, and they significantly add to accumulating evidence that conceptual knowledge is grounded in the brain's modality-specific systems.
Zotero Collections:
Motion correction of fMRI data is a widely used step prior to data analysis. In this study, a comparison of the motion correction tools provided by several leading fMRI analysis software packages was performed, including AFNI, AIR, BrainVoyager, FSL, and SPM2. Comparisons were performed using data from typical human studies as well as phantom data. The identical reconstruction, preprocessing, and analysis steps were used on every data set, except that motion correction was performed using various configurations from each software package. Each package was studied using default parameters, as well as parameters optimized for speed and accuracy. Forty subjects performed a Go/No-go task (an event-related design that investigates inhibitory motor response) and an N-back task (a block-design paradigm investigating working memory). The human data were analyzed by extracting a set of general linear model (GLM)-derived activation results and comparing the effect of motion correction on thresholded activation cluster size and maximum t value. In addition, a series of simulated phantom data sets were created with known activation locations, magnitudes, and realistic motion. Results from the phantom data indicate that AFNI and SPM2 yield the most accurate motion estimation parameters, while AFNI's interpolation algorithm introduces the least smoothing. AFNI is also the fastest of the packages tested. However, these advantages did not produce noticeably better activation results in motion-corrected data from typical human fMRI experiments. Although differences in performance between packages were apparent in the human data, no single software package produced dramatically better results than the others. The "accurate" parameters showed virtually no improvement in cluster t values compared to the standard parameters. While the "fast" parameters did not result in a substantial increase in speed, they did not degrade the cluster results very much either. The phantom and human data indicate that motion correction can be a valuable step in the data processing chain, yielding improvements of up to 20% in the magnitude and up to 100% in the cluster size of detected activations, but the choice of software package does not substantially affect this improvement.
Zotero Collections:
The ability to accurately infer others’ mental states from facial expressions is important for optimal social functioning and is fundamentally impaired in social cognitive disorders such as autism. While pharmacologic interventions have shown promise for enhancing empathic accuracy, little is known about the effects of behavioral interventions on empathic accuracy and related brain activity. This study employed a randomized, controlled and longitudinal design to investigate the effect of a secularized analytical compassion meditation program, cognitive-based compassion training (CBCT), on empathic accuracy. Twenty-one healthy participants received functional MRI scans while completing an empathic accuracy task, the Reading the Mind in the Eyes Test (RMET), both prior to and after completion of either CBCT or a health discussion control group. Upon completion of the study interventions, participants randomized to CBCT and were significantly more likely than control subjects to have increased scores on the RMET and increased neural activity in the inferior frontal gyrus (IFG) and dorsomedial prefrontal cortex (dmPFC). Moreover, changes in dmPFC and IFG activity from baseline to the post-intervention assessment were associated with changes in empathic accuracy. These findings suggest that CBCT may hold promise as a behavioral intervention for enhancing empathic accuracy and the neurobiology supporting it.
Zotero Collections:
<p>Divides the study of human attention into 3 components: alertness, selectivity, and processing capacity. Experimental techniques designed to separate these components and examine their interrelations within comparable tasks are outlined. It is shown that a stimulus may be used to increase alertness for processing all external information, to improve selection of particular stimuli, or to do both simultaneously. Development of alertness and selectivity are separable, but may go on together without interference. Moreover, encoding a stimulus may proceed without producing interference with other signals. Thus, the contact between an external stimulus and its representation in memory does not appear to require processing capacity. Limited capacity results are obtained when mental operations, E.g., response selection or rehearsal, must be performed on the encoded information. (45 ref.)</p>
Zotero Collections:
Zotero Collections:
It is proposed that concepts contain two types of properties. Context-independent properties are activated by the word for a concept on all occasions. The activation of these properties is unaffected by contextual relevance. Context-dependent properties are not activated by the respective word independent of context. Rather, these properties are activated only by relevant contexts in which the word appears. Context-independent properties form the core meanings of words, whereas context-dependent properties are a source of semantic encoding variability. This proposal lies between two opposing theories of meaning, one that argues all properties of a concept are active on all occasions and another that argues the active properties are completely determined by context. The existence of context-independent and context-dependent properties is demonstrated in two experimental settings: the property-verification task and judgments of similarity. The relevance of these property types to cross-classification, problem solving, metaphor and sentence comprehension, and the semantic-episodic distinction is discussed.
Zotero Collections:
We present a novel data smoothing and analysis framework for cortical thickness data defined on the brain cortical manifold. Gaussian kernel smoothing, which weights neighboring observations according to their 3D Euclidean distance, has been widely used in 3D brain images to increase the signal-to-noise ratio. When the observations lie on a convoluted brain surface, however, it is more natural to assign the weights based on the geodesic distance along the surface. We therefore develop a framework for geodesic distance-based kernel smoothing and statistical analysis on the cortical manifolds. As an illustration, we apply our methods in detecting the regions of abnormal cortical thickness in 16 high functioning autistic children via random field based multiple comparison correction that utilizes the new smoothing technique.
Zotero Collections:
Many investigators have hypothesized that brain response to cortisol is altered in depression. However, neural activation in response to exogenously manipulated cortisol elevations has not yet been directly examined in depressed humans. Animal research shows that glucocorticoids have robust effects on hippocampal function, and can either enhance or suppress neuroplastic events in the hippocampus depending on a number of factors. We hypothesized that depressed individuals would show 1) altered hippocampal response to exogenous administration of cortisol, and 2) altered effects of cortisol on learning. In a repeated-measures design, 19 unmedicated depressed and 41 healthy individuals completed two fMRI scans. Fifteen mg oral hydrocortisone (i.e., cortisol) or placebo (order randomized and double-blind) was administered 1 h prior to encoding of emotional and neutral words during fMRI scans. Data analysis examined the effects of cortisol administration on 1) brain activation during encoding, and 2) subsequent free recall for words. Cortisol affected subsequent recall performance in depressed but not healthy individuals. We found alterations in hippocampal response to cortisol in depressed women, but not in depressed men (who showed altered response to cortisol in other regions, including subgenual prefrontal cortex). In both depressed men and women, cortisol's effects on hippocampal function were positively correlated with its effects on recall performance assessed days later. Our data provide evidence that in depressed compared to healthy women, cortisol's effects on hippocampal function are altered. Our data also show that in both depressed men and women, cortisol's effects on emotional memory formation and hippocampal function are related.
Zotero Collections:
Pages |