Brain Mapping as a Tool to Study Neurodegeneration

Abstract

Summary: Alzheimer's disease (AD) is the most common neurodegenerative disorder for those 65 years or older; it currently affects 4.5 million in the United States and is predicted to rise to 13.2 million by the year 2050. Neuroimaging and brain mapping techniques offer extraordinary power to understand AD, providing spatially detailed information on the extent and trajectory of the disease as it spreads in the living brain. Computational anatomy techniques, applied to large databases of brain MRI scans, reveal the dynamic sequence of cortical and hippocampal changes with disease progression and how these relate to cognitive decline and future clinical outcomes. People who are mildly cognitively impaired, in particular, are at a fivefold increased risk of imminent conversion to dementia, and they show specific structural brain changes that are predictive of imminent disease onset. We review the principles and key findings of several new methods for assessing brain degeneration, including voxel-based morphometry, tensor-based morphometry, cortical thickness mapping, hippocampal atrophy mapping, and automated methods for mapping ventricular anatomy. Applications to AD and other dementias are discussed, with a brief review of related findings in other neurological and neuropsychiatric illnesses, including epilepsy, HIV/AIDS, schizophrenia, and disorders of brain development.

A complex dietary supplement augments spatial learning, brain mass, and mitochondrial electron transport chain activity in aging mice

“…3). Hippocampal function critical to memory is exceptionally sensitive to aging (Kausler 1994;Apostolova and Thompson 2007). The MWM test is considered to test hippocampal function (Vorhees and Williams 2006).…”

“…The MWM test is considered to test hippocampal function (Vorhees and Williams 2006). Neurodegeneration of the hippocampus is widely implicated in the loss of spatial memory (navigation skills), dementia, and AD (Foster 1999;Apostolova and Thompson 2007). In AD, the rate of hippocampal atrophy is 3.5-4%/year, exceeding the ∼1.6%/year loss observed in normal aging by nearly 3-fold (Jack et al 1998(Jack et al , 2000.…”

“…In AD, the rate of hippocampal atrophy is 3.5-4%/year, exceeding the ∼1.6%/year loss observed in normal aging by nearly 3-fold (Jack et al 1998(Jack et al , 2000. For normal aging and neurodegenerative conditions alike, diminishing hippocampal volume is correlated with atrophy of other brain regions, increasing ventricular space and diminished brain volume (Scahill et al 2003;Apostolova and Thompson 2007). Consequently, brain size is a strong predictor of cognitive decline, hippocampal degeneration, and risk of AD (Scahill et al 2003;Jack et al 2004).…”

Cerebellar volume in patients with dementia

“…4 Recently, the possibility of an early diagnosis of AD has brought attention to the importance of neuroimaging investigations in predementia patients. 5 Several studies using region-of-interest (ROI) and voxel-based analyses have reported reduced volumes in the hippocampus, parahippocampal gyrus, cingulate and other brain regions in patients with mild cognitive impairment (MCI) and AD. 2,[6][7][8] The spatial pattern of brain atrophy in MCI is complex and highly variable and does not always progress in a linear manner.…”

Prospects for Early Detection of Alzheimers Disease from Serial MR Images in Transgenic Mouse Models

“…Brain mapping techniques [18] can be used to quantify changes, for example in voxel-based morphometry [19,20], and more involved approaches estimate diffeomorphic changes in local brain structure [21] or construct local surface models [22] from volumetric measurements. Texture analysis is an interesting alternative [23] that has received little attention so far.…”