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Objective: The pathological cascades associated with the development of Alzheimer's disease (AD) have a common element: acidosis. T 1 rho MRI is a pH-sensitive measure, with higher values associated with greater neuropathological burden. The authors investigated the relationship between T 1 rho imaging and AD-associated pathologies as determined by available diagnostic imaging techniques., Methods: Twenty-seven participants (men, N=13, women, N=14; ages 55-90) across the cognitive spectrum (healthy control subjects [HCs] with normal cognition, N=17; participants with mild cognitive impairment [MCI], N=7; participants with mild AD, N=3) underwent neuropsychological testing, MRI (T 1 -weighted and T 1 rho [spin-lattice relaxation time in the rotating frame]), and positron emission tomography imaging ([ 11 C]Pittsburg compound B for amyloid burden [N=26] and [ 18 F]fluorodeoxyglucose for cerebral glucose metabolism [N=12]). The relationships between global T 1 rho values and neuropsychological, demographic, and imaging measures were explored., Results: Global mean and median T 1 rho were positively associated with age. After controlling for age, higher global T 1 rho was associated with poorer cognitive function, poorer memory function (immediate and delayed memory scores), higher amyloid burden, and more abnormal cerebral glucose metabolism. Regional T 1 rho values, when controlling for age, significantly differed between HCs and participants with MCI or AD in select frontal, cingulate, and parietal regions., Conclusions: Higher T 1 rho values were associated with greater cognitive impairment and pathological burden. T 1 rho, a biomarker that varies according to a feature common to each cascade rather than one that is unique to a particular pathology, has the potential to serve as a metric of neuropathology, theoretically providing a measure for assessing pathological status and for monitoring the neurodegeneration trajectory.

This study examined the efficacy of antidepressant treatment for preventing the onset of generalized anxiety disorder (GAD) among patients with recent stroke. Of 799 patients assessed, 176 were randomized, and 149 patients without evidence of GAD at the initial visit were included in this double-blind treatment with escitalopram (N=47) or placebo (N=49) or non-blinded problem-solving therapy (PST; 12 total sessions; N=53). Participants given placebo over 12 months were 4.95 times more likely to develop GAD than patients given escitalopram and 4.00 times more likely to develop GAD than patients given PST. Although these results should be considered preliminary, the authors found that both escitalopram and PST were effective in preventing new onset of post-stroke GAD.

Executive function and denial of illness were examined among 24 patients who received double-blind antidepressant treatment following stroke. Between end-of-treatment at 3 months and follow-up at 2 years, significant correlation was found between improvement in executive function and decrease in denial of illness.

The relationship of behavioral disturbance and dementia severity to activities of daily living (ADLs) in vascular dementia (VaD) was examined in baseline data for 29 VaD patients. A series of stepwise regression analyses was conducted to examine the extent to which dementia severity, apathy, disinhibition, and executive dysfunction predict ADLs (total, basic, and instrumental). For total ADLs, apathy accounted for 36% of the variance and dementia severity accounted for an additional 15%. For basic ADLs, apathy accounted for 27% of the variance. Dementia severity, executive dysfunction, and disinhibition were not significantly associated with basic ADLs. For instrumental ADLs, dementia severity accounted for 37% of the variance and apathy accounted for an additional 14%. These findings highlight the importance of apathy as an independent factor associated with functional independence beyond general cognitive abilities.

Neuropsychological manifestations of bilateral anterior cingulate cortex lesions were studied in patients treated with cingulotomy for chronic intractable pain. Cingulotomy patients more than 1 year postsurgery were contrasted with nonsurgical chronic pain patients. Patients were assessed on a neuropsychological battery, including measures of response intention, initiation, generation, and persistence. Cingulotomy patients were intact across most cognitive domains, but they showed deficits of focused and sustained attention as well as mild executive dysfunction. Self-initiated responding--including spontaneous verbal utterances and unstructured design fluency--was most impaired. Results indicate that the greatest impact of cingulotomy lesions is on response intention and self-initiated behavior, with reduced behavioral spontaneity.