Automaticity and cognitive anatomy: is word recognition "automatic"?

Recent progress in neural imaging technologies such as positron emission tomography and dense-array recording of event-related potentials has greatly increased the capacity for in vivo measurement of cognitively relevant processing activity within the human brain. Data from these neural imaging technologies can be combined with behavioral data from standard chronometric techniques to enhance computational modeling of human cognition. Applications of neural data to issues of attention and automaticity are illustrated in the domain of visual word recognition, addressing the question "Is word recognition automatic?"     

Positron emission tomography methods with potential for increased understanding of mental retardation and developmental disabilities

Positron emission tomography (PET) is a technique that enables imaging of the distribution of radiolabeled tracers designed to track biochemical and molecular processes in the body after intravenous injection or inhalation. New strategies for the use of radiolabeled tracers hold potential for imaging gene expression in the brain during development and following interventions. In addition, PET may be key in identifying the physiological consequences of gene mutations associated with mental retardation. The development of high spatial resolution microPET scanners for imaging of rodents provides a means for longitudinal study of transgenic mouse models of genetic disorders associated with mental retardation. In this review, we describe PET methodology, illustrate how PET can be used to delineate biochemical changes during brain development, and provide examples of how PET has been applied to study brain glucose metabolism in Rett syndrome, serotonin synthesis in autism, and GABAA receptors in Angelman's syndrome and Prader-Willi syndrome. Future application of PET scanning in the study of mental retardation might include measurements of brain protein synthesis in fragile X syndrome and tuberous sclerosis complex, two common conditions associated with mental retardation in which cellular mechanisms involve dysregulation of protein synthesis. Mental retardation results in life-long disability, and application of new PET technologies holds promise for a better understanding of the biological underpinnings of mental retardation, with the potential to uncover new treatment options.     

人类大脑结构和功能的性别差异：来自脑成像研究的证据

大脑的性别差异近年来受到了广泛关注。脑成像技术的出现为脑结构和脑功能性别差异的研究开辟了新的道路。借助结构磁共振成像和弥散张量成像等脑结构信息, 以及脑电图、正电子发射断层扫描技术和功能性磁共振成像等脑功能信息, 当前研究主要探讨了脑灰质、脑白质和大脑的基线活动在脑局部区域、脑子系统、全脑连接组三个层次上的性别差异及其在年龄上的发展变化。此外, 为了更好地理解脑性别差异, 当前文章还探讨了脑性别差异研究领域的一些认识误区。有关脑性别差异的研究虽然已经取得了丰富的成果, 但现有的研究结果存在很多分歧, 仍然有深入挖掘的空间。未来应该加强对具有性别特异性的心理疾病脑机制的研究, 关注基因和环境对脑性别差异的交互作用, 并利用脑功能活动动态变化的特性、以及结合多模态的脑成像技术进一步阐明脑性别差异。     

Cholinergic modulation of learning and memory in the human brain as detected with functional neuroimaging

The advent of neuroimaging methods such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) has provided investigators with a tool to study neuronal processes involved in cognitive functions in humans. Recent years have seen an increasing amount of studies which mapped higher cognitive functions to specific brain regions. These studies have had a great impact on our understanding of neuroanatomical correlates of learning and memory in the living human brain. Recently, advances were made to go beyond the use of fMRI as a pure cognitive brain mapping device. One of these advances includes the use of psychopharmacological approaches in conjunction with neuroimaging. The paper will introduce the combination of neuroimaging and psychopharmacology as a tool to study neurochemical modulation of human brain function. A review of imaging studies using cholinergic challenges in the context of explicit and implicit learning and memory paradigms is provided which show that cholinergic neurotransmission modulates task-related activity in sensory and frontal cortical brain areas.     

The physical activity experiences of men with serious mental illness: Three short stories

ObjectivesAlthough a considerable amount of research has explored the effects of physical activity on mental health, the voices of people with mental illness have been largely excluded from published reports. Through this study we aim to foreground service users’ voices in order to shed light on the personal and subjective nature of the relationship between physical activity and serious mental illness (SMI).MethodsAn interpretive case study approach was used to explore in depth the physical activity experiences of three men with SMI. Creative analytic practice was used to write three creative non-fictions which, as first-person narratives, foreground the participants’ voices.ResultsWe present three short stories in an effort to communicate participants’ personal and subjective experiences of physical activity in an accessible, engaging, and evocative manner. We hope to: (i) provide potentially motivating physical activity success stories for others who live with SMI; (ii) increase awareness among mental health professionals of the possibilities of physical activity; and (iii) provide an empathetic understanding of possibilities and problems of living with SMI which may help challenge the stigma surrounding mental illness.ConclusionsFor us, the stories communicate the diversity and difference inherent in the ways men with SMI experience physical activity. We reflect on how the short story form allows these differences to be preserved and respected. We resist making further interpretations of the stories preferring instead to encourage the reader to form her or his own conclusions.     

Cognitive neuroscience from a behavioral perspective: A critique of chasing ghosts with geiger counters

Cognitive neuroscience is a growing new discipline concerned with relating complex behavior to neuroanatomy. Relatively new advances in the imaging of brain function, such as positron emission tomography (PET), have generated hundreds of studies that have demonstrated a number of interesting but also potentially problematic brain-behavior relations. For example, cognitive neuroscientists largely favor interpretations of their data that rely on unobserved hypothetical mechanisms. Their reports often contain phraseology such as central executive, willed action, and mental imagery. As B. F. Skinner argued for decades, cognitive constructs of neurological data may yield nothing more than a conceptual nervous system.     

Neuroreceptor imaging of stress and mood disorders

Techniques such as positron emission tomography and single photon emission computed tomography allow for the imaging of neurotransmitter receptors and transporters in the brain. These tools have been used to investigate serotonergic, dopaminergic, and opioidergic function in healthy subjects as well as in patients with major depressive disorder, bipolar disorder, and other mood disorders. Pharmacologic challenges, such as amphetamine challenge, and physiologic stressors, such as pain challenge, have been used to further examine the function of these neurotransmitter systems. Neuroimaging of patient populations before and after medication treatment may be useful to understand changes in neurotransmission that accompany disease remission. As new radiotracers with higher selectivity for the various receptors and transporters are developed, imaging techniques may provide new insights into the pathophysiology of mood disorders, leading to improved diagnosis and treatment.     

Can neuroimaging really tell us what the human brain is doing? The relevance of indirect measures of population activity

Neuroimaging studies using positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) give an indication towards the localization of mental representations and processes in the human brain. It is not clear to what extent such global measures of neuronal activity, pooling across large populations of neurons, can reveal how certain computations are implemented by the neurons in such population ('computational neuroimaging'). Population activity is related tightly to single-cell activity when all neurons in the population have similar response properties. We describe some evidence from single-cell recordings in monkeys that indicates that neurons with similar response properties are not scattered randomly throughout the visual cortex. Notwithstanding this clustering, populations of nearby neurons are still rather heterogeneous, requiring some prudence in deriving single-cell response properties from population activity. The following review of recent neuroimaging studies of the visual system describes to what degree inferences about computations and representations can be drawn from these studies.     

Functional neuroimaging studies of human emotions

Neuroimaging studies with positron emission tomography and functional magnetic resonance imaging have begun to describe the functional neuroanatomy of human emotion. Taken separately, specific studies vary in task dimensions and in type(s) of emotion studied, and are limited by statistical power and sensitivity. By examining findings across studies in a meta-analysis, we sought to determine if common or segregated patterns of activations exist in different emotions and across various emotional tasks. We surveyed over 55 positron emission tomography and functional magnetic resonance imaging activation studies, which investigated emotion in healthy subjects. This paper will review observations in several regions of interest in limbic (eg, amygdala, anterior cingulate cortex) and paralimbic (eg, medial prefrontal cortex, insula) brain regions in emotional responding.     

Functional Neuroimaging in the Examination of Effects of Prenatal Alcohol Exposure

Functional neuroimaging offers the opportunity to understand the effect of prenatal alcohol exposure on the activities of the brain as well as providing a window into the relationship between neural activation and the behavioral outcomes that have been described in affected individuals. Several different methodologies have been used to examine the neurophysiological signal changes associated with different brain functions in prenatally exposed individuals and those diagnosed with fetal alcohol syndrome (FAS) or other fetal alcohol spectrum disorders (FASD). These include electroencephalography (EEG), positron emission tomography (PET), single-photon emission computed tomography (SPECT), and functional magnetic resonance imaging (fMRI). These studies demonstrate that it is feasible to use these technologies with this clinical population and that the damage to the central nervous system associated with prenatal alcohol exposure has widespread functional implications; however, currently, the literature in these areas is limited and unsystematic. Functional MRI with this clinical population has just begun to explore the implications of prenatal alcohol exposure with the first paper published in 2005. Other methodologies are similarly limited in scope. Nonetheless, these functional neuroimaging studies suggest that prenatal alcohol exposure, or a diagnosis of FAS, may lead to restrictions in neural efficiency or a global decrement in processing resources.     

Psychotherapy and neuroscience: Towards closer integration

The original aim of psychology was to study and understand the spirit—from the Latin spiritus, literally “breath.” The limitations of scientific methods in the past favoured psychology's aloofness in terms of studying the “intangible,” while medicine developed methods of examining the body (Latin corpus: essential part). Until 20 years ago, knowledge of the localization of brain functions was limited to inferences from clinical observation of brain‐lesioned patients or parallel studies of primate brains. Current neuroscience, with its integrative approach, is bringing together research from molecular through cognitive levels, and psychotherapy has benefited from these findings. Functional neuroimaging studies may make specific and more far‐reaching contributions in this respect, since cerebral dynamics may be observed in vivo and in controlled situations. Methods such as single photon emission tomography, positron emission tomography, and functional magnetic resonance imaging have been able to evaluate the neural correlates involved in psychotherapy for individuals with obsessive‐compulsive disorder, major depression, social phobia, specific phobia, and post‐traumatic disorder. Researchers have found that psychotherapy has the potential to modify dysfunctional neural circuits associated with these disorders. However, precautions are required in constructing feasible designs for neurofunctional investigations. This article reviews the 21 studies that have been published on the subject, and sets out the main advantages and limitations of the technologies used most frequently in protocols involving psychotherapies, and prerequisites for experimental designs. We also pose ways in which the findings from neuroimaging may produce knowledge to guide psychotherapeutic interventions by specifying what should be stimulated in these individuals in order to normalize deficient neural activities.     

Functional magnetic resonance imaging: Overview and methods for psychological research

Functional magnetic resonance imaging (fMRI) allows noninvasive imaging of hemodynamic changes related to neural activity. This technique can be used in single-subject designs and can provide millimeter spatial resolution and temporal resolution in the range of 5–10 sec. This paper provides a brief introduction to MRI techniques and their application to functional neuroimaging, focusing on methodological issues that are of particular concern to psychologists, including methods for presenting computerized stimuli to subjects without disrupting the scanner, experimental design issues, and statistical analysis and image processing procedures. To illustrate methodological issues, recent results from a series of studies looking at the topographic organization of visual cortex are presented. General issues concerning limitations in this technique, future directions in its development, its relationship to other neuroimaging techniques, and the role of functional neuroimaging in psychological research are addressed in the Discussion.     

Reduced prefrontal and increased subcortical brain functioning assessed using positron emission tomography in predatory and affective murderers

There appear to be no brain imaging studies investigating which brain mechanisms subserve affective, impulsive violence versus planned, predatory violence. It was hypothesized that affectively violent offenders would have lower prefrontal activity, higher subcortical activity, and reduced prefrontal/subcortical ratios relative to controls, while predatory violent offenders would show relatively normal brain functioning. Glucose metabolism was assessed using positron emission tomography in 41 comparisons, 15 predatory murderers, and nine affective murderers in left and right hemisphere prefrontal (medial and lateral) and subcortical (amygdala, midbrain, hippocampus, and thalamus) regions. Affective murderers relative to comparisons had lower left and right prefrontal functioning, higher right hemisphere subcortical functioning, and lower right hemisphere prefrontal/subcortical ratios. In contrast, predatory murderers had prefrontal functioning that was more equivalent to comparisons, while also having excessively high right subcortical activity. Results support the hypothesis that emotional, unplanned impulsive murderers are less able to regulate and control aggressive impulses generated from subcortical structures due to deficient prefrontal regulation. It is hypothesized that excessive subcortical activity predisposes to aggressive behaviour, but that while predatory murderers have sufficiently good prefrontal functioning to regulate these aggressive impulses, the affective murderers lack such prefrontal control over emotion regulation. © 1998 John Wiley & Sons, Ltd.     

Brain Development During the Preschool Years

The preschool years represent a time of expansive mental growth, with the initial expression of many psychological abilities that will continue to be refined into young adulthood. Likewise, brain development during this age is characterized by its ??blossoming?? nature, showing some of its most dynamic and elaborative anatomical and physiological changes. In this article, we review human brain development during the preschool years, sampling scientific evidence from a variety of sources. First, we cover neurobiological foundations of early postnatal development, explaining some of the primary mechanisms seen at a larger scale within neuroimaging studies. Next, we review evidence from both structural and functional imaging studies, which now accounts for a large portion of our current understanding of typical brain development. Within anatomical imaging, we focus on studies of developing brain morphology and tissue properties, including diffusivity of white matter fiber tracts. We also present new data on changes during the preschool years in cortical area, thickness, and volume. Physiological brain development is then reviewed, touching on influential results from several different functional imaging and recording modalities in the preschool and early school-age years, including positron emission tomography (PET), electroencephalography (EEG) and event-related potentials (ERP), functional magnetic resonance imaging (fMRI), magnetoencephalography (MEG), and near-infrared spectroscopy (NIRS). Here, more space is devoted to explaining some of the key methodological factors that are required for interpretation. We end with a section on multimodal and multidimensional imaging approaches, which we believe will be critical for increasing our understanding of brain development and its relationship to cognitive and behavioral growth in the preschool years and beyond.     

抑郁症的脑功能异常:来自静息态功能磁共振成像的证据

静息态功能磁共振成像是指在静息状态下测量的BOLD信号,即受试者安静地躺在扫描仪中,不给受试者任何特定的任务,受试者也不用做任何反应,此时受试者的大脑活动处于自发状态。通过使用该技术可以为抑郁症发作的临床现象提供神经影像学依据,以期为将来抑郁症的治疗提供生物标记。因此,本文综述了大量抑郁症患者在静息态脑功能方面的差异研究,发现了单、双相抑郁症,首、复发抑郁症,早发性、晚发性抑郁症,难治、非难治性抑郁症等不同类型的抑郁症在包括局部一致性(Re Ho)和低频振幅(ALFF)在内的功能分化以及包括功能连接密度(FCD)、功能同伦(VMHC)、复杂网络(Complex Network)和ROI功能连接在内的功能整合两大指标的改变。     

Where the Rainbow Speaks and Catches the Sun

Abstract

Living with a neurobiological brain disorder, commonly known as a mental illness, requires a lifetime of diligent work toward recovery and wellness. This paper outlines the story of one occupational therapist's journey with her own mental illness. She prefers to call her own road of “recovery” one of “discovery,” as it has led her to discover true talents and gifts (strengths) even amongst encounters with old models that emphasize weaknesses and disability over abilities and capabilities. The following journey unfolds as advances in research, changes in services, increased focus on consumer as leader and increased tools and resources available lead the way toward a more positive ability to live a purposeful life, engaging in meaningful activities in spite of an illness. This paper gives a personal account as a tool to be used by other therapists as they travel along their own treatment journeyswhether with, or as consumers, of mental health services.     

Effects of Simulated Learning and Facilitated Debriefing on Student Understanding of Mental Illness

Occupational therapy educators have studied various methods regarding student attitudes towards people with disabling conditions. Among the methods that have been studied is simulated learning. This paper describes the effects of a simulated learning exercise and facilitated debriefing on occupational therapy student understanding of mental illness. Results indicate that students had significant change relative to understanding that mental illnesses are brain diseases that respond to treatment (p < .01) on the post-test. Themes derived from qualitative data revealed that students believed that the learning experience increased their understanding, empathy, and insight into daily life with a mental illness.     

Advanced microscopic imaging methods to investigate cortical development and the etiology of mental retardation

Studies on human patients and animal models of disease have shown that disruptions in prenatal and early postnatal brain development are a root cause of mental retardation. Since proper brain development is achieved by a strict spatiotemporal control of neurogenesis, cell migration, and patterning of synapses, abnormalities in one or more of these events during prenatal development can lead to cognitive dysfunction after birth. Many of underlying causes of mental retardation must therefore be studied in developing brains. To aid in this research, live imaging using laser scanning microscopy (LSM) has recently allowed neuroscientists to delve deeply into the complex three-dimensional environment of the living brain to record dynamic cellular events over time. This review will highlight recent examples of how LSM is being applied to elucidate both normal and abnormal cortical development.     

Brain connectomics: time for a molecular imaging perspective?

In the past two decades brain connectomics has evolved into a major concept in neuroscience. However, the current perspective on brain connectivity and how it underpins brain function relies mainly on the hemodynamic signal of functional magnetic resonance imaging (MRI). Molecular imaging provides unique information inaccessible to MRI-based and electrophysiological techniques. Thus, positron emission tomography (PET) has been successfully applied to measure neural activity, neurotransmission, and proteinopathies in normal and pathological cognition. Here, we position molecular imaging within the brain connectivity framework from the perspective of timeliness, validity, reproducibility, and resolution. We encourage the neuroscientific community to take an integrative approach whereby MRI-based, electrophysiological techniques, and molecular imaging contribute to our understanding of the brain connectome.     

IGT-Open: An open-source,computerized version of the Iowa Gambling Task

The Iowa Gambling Task (IGT) is commonly used to understand the processes involved in decision-making. Though the task was originally run without a computer, using a computerized version of the task has become typical. These computerized versions of the IGT are useful, because they can make the task more standardized across studies and allow for the task to be used in environments where a physical version of the task may be difficult or impossible to use (e.g., while collecting brain imaging data). Though these computerized versions of the IGT have been useful for experimentation, having multiple software implementations of the task could present reliability issues. We present an open-source software version of the Iowa Gambling Task (called IGT-Open) that allows for millisecond visual presentation accuracy and is freely available to be used and modified. This software has been used to collect data from human subjects and also has been used to run model-based simulations with computational process models developed to run in the ACT-R architecture.