Cholinergic Receptor Binding in Alzheimer Disease and Healthy Aging: Assessment In Vivo with Positron Emission Tomography Imaging.

Objective: To compare regional nicotinic cholinergic receptor binding in older adults with Alzheimer disease (AD) and healthy older adults in vivo and to assess relationships between receptor binding and clinical symptoms.

Methods: Using cross-sectional positron emission tomography (PET) neuroimaging and structured clinical assessment, outpatients with mild to moderate AD (N = 24) and healthy older adults without cognitive complaints (C group; N = 22) were studied. PET imaging of α4β2* nicotinic cholinergic receptor binding using 2-[F]fluoro-3-(2(S)azetidinylmethoxy)pyridine (2FA) and clinical measures of global cognition, attention/processing speed, verbal memory, visuospatial memory, and neuropsychiatric symptoms were used.

Beta modulation reflects name retrieval in the human anterior temporal lobe: an intracranial recording study.

Naming people, places, and things is a fundamental human ability that is often impaired in patients with language-dominant anterior temporal lobe (ATL) dysfunction or ATL resection as part of epilepsy treatment. Convergent lines of evidence point to the importance of the ATL in name retrieval. The physiologic mechanisms that mediate name retrieval in the ATL, however, are not well understood.

Neurobiology of delusions, memory, and insight in Alzheimer disease.

Objective: Delusional thoughts are common among patients with Alzheimer disease (AD) and may be conceptually linked to memory deficits (cannot recall accurate information, which leads to inaccurate beliefs) and poor insight (unable to appreciate the illogic of beliefs). This study's goals were to examine the clinical associations among delusions, memory deficits, and poor insight; explore neurobiologic correlates for these symptoms; and identify shared mechanisms.

Methods: In a cross-sectional analysis, 88 outpatients with AD (mean Mini-Mental State Exam score: 19.

A critical window of CAG repeat-length correlates with phenotype severity in the R6/2 mouse model of Huntington's disease.

The R6/2 mouse is the most frequently used model for experimental and preclinical drug trials in Huntington's disease (HD). When the R6/2 mouse was first developed, it carried exon 1 of the huntingtin gene with ~150 cytosine-adenine-guanine (CAG) repeats. The model presented with a rapid and aggressive phenotype that shared many features with the human condition and was particularly similar to juvenile HD.