Neuroimaging and Neurolaw: Drawing the Future of Aging

Abstract

Human brain-aging is a complex, multidimensional phenomenon. Knowledge of the numerous aspects that revolve around it is therefore essential if not only the medical issues, but also the social, psychological, and legal issues related to this phenomenon are to be managed correctly. In the coming decades, it will be necessary to find solutions to the management of the progressive aging of the population so as to increase the number of individuals that achieve successful aging. The aim of this article is to provide a current overview of the physiopathology of brain aging and of the role and perspectives of neuroimaging in this context. The progressive development of neuroimaging has opened new perspectives in clinical and basic research and it has modified the concept of brain aging. Neuroimaging will play an increasingly important role in the definition of the individual's brain aging in every phase of the physiological and pathological process. However, when the process involved in age-related brain cognitive diseases is being investigated, factors that might affect this process on a clinical and behavioral level (genetic susceptibility, risks factors, endocrine changes) cannot be ignored but must, on the contrary, be integrated into a neuroimaging evaluation to ensure a correct and global management, and they are therefore discussed in this article. Neuroimaging appears important to the correct management of age-related brain cognitive diseases not only within a medical perspective, but also legal, according to a wider approach based on development of relationship between neuroscience and law. The term neurolaw, the neologism born from the relationship between these two disciplines, is an emerging field of study, that deals with various issues in the impact of neurosciences on individual rights. Neuroimaging, enhancing the detection of physiological and pathological brain aging, could give an important contribution to the field of neurolaw in elderly where the full control of cognitive and volitional functions is necessary to maintain a whole series of rights linked to legal capacity. For this reason, in order to provide the clinician and researcher with a broad view of the brain-aging process, the role of neurolaw will be introduced into the brain-aging context.

Keywords: Alzheimer's disease; aging-brain; geriatric endocrinology; magnetic resonance imaging; neuroimaging; neurolaw; positron emission tomography; vascular risk factors.

Figure 1

A multidimensional geometric model of cognitive brain aging. Each geometric figure contains the set of factors that affect the multidimensional phenomenon of aging. The number of sides of each geometric figure corresponds to the number of factors contained in it, e.g., the hexagon contains the 6 main cognition factors. Bidirectional arrows indicate an effect of the factors upon each other and on the aging phenomenon.

Figure 2

Hybrid brain PET/MRI imaging (Biograph mMR, Siemens) in a normal subject. The top picture shows anatomical MRI 3D T1-weighted images on the coronal, axial and sagittal slices. In the figure above, a metabolic 18FDG PET image of the same individual is combined with the MRI image to obtain information on the morphology, anatomy and metabolism of the brain.

Figure 3

Neuroimaging of cerebrovascular disease in the aging brain. The figure shows a brain MRI study of a patient with risk factors affected by cognitive disorders. The images above (T2-weighted axial slices) and below (T1-weighted axial slices, after contrast enhancement) show diffuse, punctate deep white matter foci, hyperintense T2-weighted images, with a low signal intensity on T1-weighted images and without contrast enhancement, suggesting cerebral small vessel vascular disease.

Figure 4

Hybrid PET/MRI imaging (Biograph mMR, Siemens). The picture above shows MRI 3D T1-weighted and 18FDG PET coronal, axial and sagittal slices in a patient affected by progressive speech disorder. The combined structural and metabolic image shows focal atrophy and reduced glucose metabolism in the left temporal lobe (white arrows), suggesting a diagnosis of Primary Progressive Aphasia, a rare form of dementia. The picture below shows MRI 3D T1-weighted and a 18F-flumetamole PET coronal, axial and sagittal slices in the same patient. The combined structural and molecular (Aß amyloid accumulation) image shows a diffuse increase in Aß amyloid deposits in the cortex, supporting the diagnosis of brain neurodegenerative disease.