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Imaging Cognitive Decline in Aging: Predicting Decline with Structural Imaging

Jeffrey Kaye

in Imaging the Aging Brain

The focus of this chapter is predicting cognitive decline or dementia in normal older people using structural imaging. Key questions addressed include the following: What are the major methods, both ... More

The focus of this chapter is predicting cognitive decline or dementia in normal older people using structural imaging. Key questions addressed include the following: What are the major methods, both clinical and imaging, that may help us to predict decline? What underlying pathologies do structural changes preceding decline suggest are developing in the brain? What is the evidence from structural studies that anatomical changes are present before behavioral ones or precede the diagnosis of mild cognitive impairment or dementia? Does imaging provide information about the pace of future decline? What are the limitations of these studies? Finally, what are the implications of structural imaging outcomes for application to the conduct of treatment studies and future research?Less

Frontotemporal dementia and the orbitofrontal cortex

Po H. Lu, Negar Khanlou, and Jeffrey L. Cummings

in The Orbitofrontal Cortex

Patients with frontotemporal dementia (FTD) manifest severe behavioral and personality alterations associated with orbitofrontal cortex (OFC) dysfunction. This chapter provides a review of the ... More

Patients with frontotemporal dementia (FTD) manifest severe behavioral and personality alterations associated with orbitofrontal cortex (OFC) dysfunction. This chapter provides a review of the clinical features, neuropathology, neuroimaging, genetics, and neuropsychology of FTD as well as presenting two prototypical cases that provide a clinical picture of the disorder. Neuropathological and neuroimaging studies have identified the OFC as the brain region most prominently involved in the frontal-variant of FTD. The neuroanatomy, circuitry, and functions of the OFC are summarized, emphasizing its role in emotional and social cognition. Theories involving deficits in recognition of emotional expression, decision-making, and theory of mind have been proposed to explain the mechanism underlying the clinical expression of FTD, and the OFC is intimately involved in studies examining the neural basis underlying these deficits.Less

Novel Approaches to the Assessment of Frontal Damage and Executive Deficits in Traumatic Brain Injury

Brian Levine, Douglas I. Katz, Lauren Dade, and Sandra E. Black

in Principles of Frontal Lobe Function

Traumatic brain injury (TBI) is a major cause of frontal brain damage. This chapter describes interrelated streams of research aimed at improving the specificity of behavioral and brain imaging ... More

Traumatic brain injury (TBI) is a major cause of frontal brain damage. This chapter describes interrelated streams of research aimed at improving the specificity of behavioral and brain imaging assessment of TBI. It begins with a brief review of TBI neuropathology. It then examines the cognitive and behavioral consequences of traumatic brain injury.Less

Brain Temperature Regulation During Normal Neural Function and Neuropathology

Eugene A. Kiyatkin

in Neurovascular Medicine: Pursuing Cellular Longevity for Healthy Aging

This chapter deals with brain temperature as a physiological parameter, which is determined primarily by neural metabolism, regulated by cerebral blood flow, and affected by various environmental ... More

This chapter deals with brain temperature as a physiological parameter, which is determined primarily by neural metabolism, regulated by cerebral blood flow, and affected by various environmental factors and drugs. First, normal fluctuations in brain temperature that are induced by salient environmental stimuli and occur during motivated behavior at stable normothermic conditions are examined. On the basis of thermorecording data obtained in animals, the range of physiological fluctuations in brain temperature, their underlying mechanisms, and relations to body temperatures are described. The temperature dependence of neural activity and the dual “functions” of temperature as a reflection of metabolic brain activity and as a factor that affects this activity are considered. Third, pharmacological brain hyperthermia is discussed, focusing on the effects of psychomotor stimulants, highly popular drugs of abuse that increase brain metabolism, diminish heat dissipation, and may induce pathological brain overheating. The role of brain hyperthermia in leakage of the blood-brain barrier, development of brain edema, acute abnormalities of neural cells, and neurotoxicity, is also examined.Less

Neurodegenerative disease: With Harry Baker

James W. Fawcett, Anne E. Rosser, and Stephen B. Dunnett

in Brain Damage, Brain Repair

Most dementias are associated with a widespread pattern of atrophy in the forebrain, which is most apparent as a reduction in the weight of the brain measured post-mortem. As the brain undergoes loss ... More

Most dementias are associated with a widespread pattern of atrophy in the forebrain, which is most apparent as a reduction in the weight of the brain measured post-mortem. As the brain undergoes loss of cells, there is a thinning of the neocortex, and an associated flattening of the sulci on the surface of the brain and the ventricles in its depths. Dementia can come about through a number of different causes. In a series of studies in the 1950s and 1960s, Sir Martin Roth and his colleagues at the University of Newcastle undertook a systematic evaluation of the nature of the post-mortem pathology in a large series of patients dying (both with and without dementia) in a psychogeriatric hospital. These studies highlighted the fact that the cognitive disturbances of senile dementia can be associated with a number of distinct patterns of neuropathology, associated with different causes and disease processes.Less

Alzheimer's disease

Andrew J. Larner

in Cognitive Neurology: A clinical textbook

The diagnosis of Alzheimer's disease (AD) may be possible, probable, or definite. In clinical practice, most diagnoses are of probable AD: dementia is established on the basis of clinical examination ... More

The diagnosis of Alzheimer's disease (AD) may be possible, probable, or definite. In clinical practice, most diagnoses are of probable AD: dementia is established on the basis of clinical examination and neuropsychological testing, and there is evidence of progressive worsening of memory and other cognitive functions without disturbance of consciousness. Supportive features include impaired activities of daily living (ADL), behavioural changes, and a positive family history of similar disease, particularly if confirmed by neuropathology. Supportive investigations include a normal cerebrospinal fluid (CSF), normal or non-specific electroencephalographic (EEG) changes, and cerebral atrophy on computerized tomography (CT) with progression documented by serial observation. Other features deemed consistent with probable AD include plateaus in the course of the illness, various associated behavioural features, and certain neurological signs including myoclonus and seizures. Features that make the diagnosis uncertain or unlikely include sudden onset, focal neurological findings, or seizures early in the course, though none of these excludes the diagnosis.Less

Visual development following treatment of a unilateral infantile cataract

Ronald G. Boothe

in Infant Vision

An understanding of the ways in which vision develops following treatment of an infantile cataract is of considerable interest to a broad spectrum of basic scientists and clinicians. Devising ... More

An understanding of the ways in which vision develops following treatment of an infantile cataract is of considerable interest to a broad spectrum of basic scientists and clinicians. Devising improved methods for treatment, or ideally methods for prevention, of the amblyopia that typically develops following the surgical removal of the cataract poses a significant challenge for clinicians. Psychophysicists are interested in the precise nature of the perceptual deficits that sometimes develop in these children. Neuroscientists are particularly interested in questions regarding the neuropathology in the visual pathways in the brain that correlate with reduced visual function. Developmental psychologists are intrigued by the implications this topic has for broad issues having to do with the relative importance of ‘nature versus nurture’ in guiding development. This chapter attempts to summarize some of the main findings from the literatures from all of these disciplines in order to synthesize an understanding of visual development in children being treated for infantile cataracts.Less

Orientations

Lawrence Cohen

in No Aging in India: Alzheimer's, The Bad Family, and Other Modern Things

This chapter discusses Zagreb Tamasha, an article in India Today about Alzheimer's disease, neuropathology, cerebral softening in the tropics, senility, dementia, and the city of Varanasi. Tamasha in ... More

This chapter discusses Zagreb Tamasha, an article in India Today about Alzheimer's disease, neuropathology, cerebral softening in the tropics, senility, dementia, and the city of Varanasi. Tamasha in Hindi is a commotion, a performance—song and dance, tragedy, burlesque, and romance strung together with lots of noise. In 1988, anthropologists from around the world convened in Zagreb for a global conference. Several sessions were devoted to old age. Meanwhile, a 1985 article India Today reported on a search for the characteristic neuropathological signs of Alzheimer's disease in Indian brains. A team of neurologists and neuropathologists concluded that some sort of protective factor might be preventing the occurrence of Alzheimer's disease in India.Less

Animal Models of the Maternal Infection Risk Factor for Schizophrenia

Paul H. Patterson

in The Origins of Schizophrenia

This chapter presents animal experiments that study maternal infection as a risk factor for schizophrenia. Exposure of pregnant mice to a strain of human influenza virus results in offspring with ... More

This chapter presents animal experiments that study maternal infection as a risk factor for schizophrenia. Exposure of pregnant mice to a strain of human influenza virus results in offspring with several histologic abnormalities in the hippocampus and cortex. These offspring also display a spatially restricted deficit in Purkinje cells, which are commonly found in autism and also occur in schizophrenia, as well as smaller and more densely packed pyramidal cells, a finding also reminiscent of schizophrenia pathology. Moreover, rodent models of viral and bacterial maternal infection yield offspring with a series of abnormal behaviors and neuropathology consistent with those found in schizophrenia. These models are being used to investigate the molecular and cellular pathways that mediate the effects of maternal infection on fetal brain development.Less

The Mnemonic Brain: Neuroimaging, Neuropharmacology, and Disorders of Memory

Paul M. Matthews

in The Memory Process: Neuroscientific and Humanistic Perspectives

This chapter discusses the use of neuropathology and neuroimaging in memory studies and how research applying these tools led efforts to relate a psychological view of memory to an understanding of ... More

This chapter discusses the use of neuropathology and neuroimaging in memory studies and how research applying these tools led efforts to relate a psychological view of memory to an understanding of the brain and the way it works. It also considers how imaging of memory-related phenomena at a systems level can be related to underlying cellular and molecular mechanisms. Integration across these levels provides the basis for current efforts to develop treatments that may limit or even reverse disorders of memory. The complexity of the challenge and even the definition of what we consider a disorder of memory are illustrated by the concluding clinical vignettes. These highlight the need for consilience in memory studies if we are powerfully and humanely to translate our understanding of memory into strategies for improving health and well-being.Less

Memory Images: Models of Reason in the Liberal Age

in Vienna in the Age of Uncertainty: Science, Liberalism, and Private Life

This chapter discusses the model of the reasoning mind. Hunting was a favorite pastime among the Exner men. It was also a favorite diversion of Crown Prince Rudolph, Adolf Exner's former pupil. As an ... More

This chapter discusses the model of the reasoning mind. Hunting was a favorite pastime among the Exner men. It was also a favorite diversion of Crown Prince Rudolph, Adolf Exner's former pupil. As an exercise in the masculine virtues of liberal individualism, hunting served the Exners as one defense against “the herd existence.” Sigmund Exner's neurological research in the 1880s depended literally as well as symbolically on liberal power in Austria. The hunter provided the patterns for Sigmund's self-fashioning as a scientist and for his standard of liberal rationality. His study of cerebral localization led him to a great mystery of neuropathology. Exner's theory of visual memory naturalized a model of reason characteristic of Austrian science and liberalism. The culture of the summer retreat provided the Exners with embodied ideals of liberal morality and reason.Less