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Mounting behavioral evidence suggests that declines in both representational quality and controlled retrieval processes contribute to episodic memory decline with age. The present study sought neural evidence for age-related change in these factors by measuring neural differentiation during encoding of paired associates and changes in regional blood oxygenation level–dependent activity and functional connectivity during retrieval conditions that placed low (intact pairs) and high (recombined pairs) demands on controlled retrieval processes. Pattern similarity analysis revealed age-related declines in the differentiation of stimulus representations at encoding, manifesting as both reduced pattern similarity between closely related events and increased pattern similarity between distinct events. During retrieval, both groups increased recruitment of areas within the core recollection network when endorsing studied pairs, including the hippocampus and angular gyrus. In contrast, only younger adults increased recruitment of, and hippocampal connectivity with, lateral prefrontal regions during correct rejections of recombined pairs. These results provide evidence for age-related changes in representational quality and in the neural mechanisms supporting memory retrieval under conditions of high, but not low, control demand. • Memory decline with age may relate to representational quality and strategic retrieval. • We tested memory performance along with univariate and multivariate fMRI measures. • Neural evidence for reduced representational specificity at encoding and retrieval. • Deficits also observed in neural mechanisms underlying controlled strategic retrieval. • Memory decline linked to representational content and strategic retrieval processes. [ABSTRACT FROM AUTHOR]

Healthy aging is typically accompanied by cognitive decline. Previous work has shown that engaging in multiple, non-work activities during midlife can have a protective effect on cognition several decades later, rendering it less dependent on brain structural health; the definition of "cognitive reserve". Other work has shown that increasing age is associated with reduced segregation of large-scale brain functional networks. Here we tested the hypothesis that functional segregation (SyS) mediates this effect of middle-aged lifestyle on late-life cognition. We used fMRI data from three tasks in the CamCAN dataset, together with cognitive data on fluid intelligence, episodic memory, and retrospective lifestyle data from the Lifetime of Experiences Questionnaire (LEQ). In all three tasks, we showed that SyS related to fluid intelligence even after adjusting for the (nonlinear) age effects. However, we found no evidence that SyS in late-life mediated the relationship between non-specific (non-occupation) midlife activities and either measure of cognition in late-life. Thus, the brain correlates of cognitive reserve arising from mid-life activities remain to be discovered. • System segregation (SyS) is stable across different brain states. • SyS is negatively associated with age. • Fluid intelligence, but not episodic memory, was robustly predicted by SyS. • Late life SyS was not associated with midlife outside of work activities. [ABSTRACT FROM AUTHOR]

This study sought to determine the effects of ageing on the in vivo micturition characteristics of male Wistar rats and to assess whether they might be replicated in young rats by using the neurotoxin DSP-4 to lesion locus coeruleus-derived noradrenergic pathways projecting to spinal cord nuclei controlling micturition. Significant age-related changes in micturition patterns were observed. There was a loss of a diurnal rhythm in micturition patterns and a large increase in voided volume, maximal between 21 and 24 months, which was paralleled by an increased water intake. DSP-4 lesions neither altered micturition patterns nor water intake in the young adult rat. DSP-4 induced changes in the pattern of tyrosine hydroxylase-like immunoreactivity (TH-LI), most notably almost complete depletion of TH-LI in the dorsolateral nucleus and retention of TH-LI in lumbosacral autonomic preganglionic nuclei, did not mimic the changes in the pattern of TH-LI seen in aged rats. [Copyright &y& Elsevier]

Objective: We explored the associations of dual sensory impairment (DSI) with long-term depressive and anxiety symptoms as well as low perceived social support (LPSS) as a modifier of these associations.Methods: Multinomial logistic regression models were used to examine the associations of DSI and single sensory impairment (hearing [pure-tone average > 25 dB] and vision [impaired visual acuity and/or contrast sensitivity]) with long-term depressive symptom (≥8 on the 10-item Center for Epidemiologic Studies-Depression Scale) and anxiety symptom (present on the Hopkins Symptom Checklist) latent classes from group-based trajectory models (rare/never; mild/moderate increasing; chronically high) among 2102 Health, Aging and Body Composition Study participants (mean age:74.0 ± 2.8 years; 51.9 % female) over 10 years. Models were adjusted by demographic characteristics and cardiovascular risk factors, and LPSS. An additional model evaluated the two-way interaction between DSI and LPSS.Results: DSI was associated with increased risk of being chronically depressed (Risk Ratio, RR = 1.99, 95 % Confidence Interval, CI: 1.25, 3.17), not mild/moderate increasingly depressed (RR = 1.25, 95 % CI: 0.91, 1.71). DSI had increased risk of being mild/moderate increasingly anxious (RR = 1.60, 95 % CI: 1.16, 2.19) and chronically anxious (RR = 1.86, 95 % CI: 1.05, 3.27) groups, as compared to no impairments. Hearing impairment was associated with being mild/moderate increasingly anxious (RR = 1.34, 95 % CI: 1.01, 1.79). No other associations were found for single sensory impairments. LPSS did not modify associations.Limitations: Sensory measures were time-fixed, and LPSS, depression and anxiety measures were self-reported.Conclusions: Future research is warranted to determine if DSI therapies may lessen long-term chronically high depressive and anxiety symptoms. [ABSTRACT FROM AUTHOR]

Much evidence suggests that the Hippocampus is necessary for learning novel associations. Contrary to this, Sharon, Moscovitch, and Gilboa (2011) reported four amnesic patients with Hippocampal damage who maintained the capacity to learn novel object-name associations when trained with a ‘fast-mapping’ (FM) technique. This technique therefore potentially offers an alternative route for learning novel information in populations experiencing memory problems. We examined this potential in healthy ageing, by comparing 24 Older and 24 Young participants who completed a FM procedure very similar to Sharon et al. (2011) . As expected, the Older group showed worse memory than the Young group under standard explicit encoding (EE) instructions. However, the Older group continued to show worse performance under the FM procedure, with no evidence that FM alleviated their memory deficit. Indeed, performance was worse for the FM than EE condition in both groups. Structural MRI scans confirmed reduced Hippocampal grey-matter volume in the Older group, which correlated with memory performance across both groups and both EE/FM conditions. We conclude FM does not help memory problems that occur with normal ageing, and discuss theoretical implications for memory theories. [ABSTRACT FROM AUTHOR]

Abstract: Age-related volume loss; increased skin laxity, fat loss, and redistribution; and diminished support from underlying muscle and bone result in the observable and sometimes profound changes seen in the aging face. Aging also is associated with functional changes in the skin, such as dermal atrophy with diminished fibroblastic activity, decreased collagen production, and altered clastin. Dermal fillers, such as bovine, human, and purified porcine collagen; hyaluronic acids; calcium hydroxylapatite; and injectable medical devices (eg, poly-L-lactic acid), are used commonly for facial rejuvenation. Soft-tissue augmentation with fermal fillers and injectable medical devices has gained widespread acceptance as an alternative to more aggressive, invasive treatment of the aging face. Technique, knowledge, expertise with fillers, proper patient assessment, a well-formulated treatment plan with access to agents for superficial, moderate, and deep rhytides, and volume restoration provide the necessary ingredients for optimal soft-tissue augmentation while minimizing complications. [Copyright &y& Elsevier]

Abstract: Older adults often exhibit elevated false recognition for events that never occurred, while simultaneously experiencing difficulty in recognizing events that actually occurred. It has been proposed that reduced recollection in conjunction with an over-reliance on familiarity may contribute to this pattern of results. This explanation is somewhat inconsistent, however, with recent evidence suggesting that familiarity and associated neural activity are reduced in healthy aging. Alternatively, given that illusory memory may be based, in part, on veridical memory processes (recollection/familiarity), one might predict that older adults exhibit enhanced false alarm rates because the neural signatures associated with true recognition (hits) and false recognition (false alarms) are less distinguishable in old than in young adults. Here, we used event-related fMRI to measure the effects of aging on neural activity associated with recollection, familiarity and familiarity-based false alarms for objects in young and older adults. Compared to young adults, older adults exhibited elevated false alarm rates and impaired behavioral indices of recollection and familiarity. Imaging data showed that older adults exhibited reduced recollection effects in the left parietoccipital cortex. Furthermore, while similar regions in frontal, parietal, lateral and inferior temporal cortices contributed to familiarity-based true and false recognition, reduced familiarity-related activity in frontal and inferior temporal regions in the older adults resulted in decreased differentiation between true and false recognition effects in this group. Our results suggest that reductions in neural activity associated with both recollection and familiarity for studied items may contribute to elevated false recognition in older adults, via reduced differentiation between the neural activity associated with true and false memory. [ABSTRACT FROM AUTHOR]

Abstract: Measurement of cerebral autoregulation is important for the evaluation and management of a number of clinical disorders that affect cerebral blood flow. We currently lack simple bedside measures that mimic common physiologic stresses. Therefore, we evaluated a new sit-to-stand technique as an alternative method to the frequently-used thigh-cuff technique in healthy volunteers. Continuous middle cerebral artery (MCA) blood flow velocities (BFV) and arterial blood pressure (ABP) were measured in response to standing from a sitting position, or rapid thigh-cuff deflation in 24 healthy subjects (50 ± 22 y). Autoregulatory index (ARI) was calculated as the BFV response for step changes in ABP using a second-order differential equation with a set of parameters that can be used to grade the performance of autoregulation. Of these 24 subjects, 30% could tolerate only two thigh-cuffs and refused to proceed with the third cuff, whereas none of our subjects had any difficulty with performing the three sit-to-stand trials. The two techniques produced similar changes in mean ABP, but the times to nadir of the blood pressure and BFV were significantly faster for the thigh-cuff. The mean group ARIs were similar between the two techniques. Although between-subjects variability was higher for sit-to-stand ARIs, the within-subject sit-to-stand ARI variability was small. Thus, for the assessment of cerebral autoregulation, the sit-to-stand procedure is well tolerated and produces ARI values that have low within-subject variability. The sit-to-stand technique appears to be a suitable measure of individual ARI values for inferring dynamic cerebral autoregulation. E-mail: fsorond@partners.org [Copyright &y& Elsevier]

Mnemonic discrimination deficits, or impaired ability to discriminate between similar events in memory, is a hallmark of cognitive aging, characterised by a stark age-related increase in false recognition. While individual differences in mnemonic discrimination have gained attention due to potential relevance for early detection of Alzheimer's disease, our understanding of the component processes that contribute to variability in task performance across older adults remains limited. The present investigation explores the roles of representational quality, indexed by perceptual discrimination of objects and scenes with overlapping features, and strategic retrieval ability, indexed by standardised tests of executive function, to mnemonic discrimination in a large cohort of older adults (N=124). We took an individual differences approach and characterised the contributions of these factors to performance under Forced Choice (FC) and Yes/No (YN) recognition memory formats, which place different demands on strategic retrieval. Performance in both test formats declined with age. Accounting for age, individual differences in FC memory performance were best explained by perceptual discrimination score, whereas YN memory performance was best explained by executive functions. A linear mixed model and dominance analyses confirmed the relatively greater importance of perceptual discrimination over executive functioning for FC performance, while the opposite was true for YN. These findings highlight parallels between perceptual and mnemonic discrimination in aging, the importance of considering demands on executive functions in the context of mnemonic discrimination, and the relevance of test format for modulating the impact of these factors on performance in older adults. [ABSTRACT FROM AUTHOR]

Abstract The locus coeruleus (LC), the major origin of noradrenergic modulation of the central nervous system, may play an important role in neuropsychiatric disorders including Parkinson's disease and Alzheimer's disease. The pattern of age-related change of the LC across the life span is unclear. We obtained normalized, mean LC signal intensity values, that is, contrast ratios (CRs), from magnetization transfer–weighted images to investigate the relationship between LC CR and age in cognitively normal healthy adults (N = 605, age range 18–88 years). Study participants were part of the Cambridge Centre for Ageing and Neuroscience—an open-access, population-based data set. We found a quadratic relationship between LC CR and age, the peak occurring around 60 years, with no differences between males and females. Subregional analyses revealed that age-related decline in LC CR was confined to the rostral portion of the LC. Older adults showed greater variance in overall LC CR than younger adults, and the functional and clinical implications of these observed age-related differences require further investigation. Visualization of the LC in this study may inform how future scanning parameters can be optimized, and provides insight into how LC integrity changes across the life span. Highlights • A quadratic relationship between locus coeruleus signal intensity and age was found. • No differences between males and females were observed. • Older adults had higher variance than younger adults. • The functional and clinical implications of these changes require further research. [ABSTRACT FROM AUTHOR]

Cognitive functioning was compared in elderly patients with schizophrenia, elderly patients with probable Alzheimer''s disease (AD), and matched healthy controls using a brief neuropsychological battery. Both schizophrenia and AD patients demonstrated marked impairment as compared to controls, with the profile of neuropsychological deficits in both disorders appearing remarkably similar. Only visual confrontation naming, verbal delayed recall, and rate of forgetting (i.e. savings score) significantly differentiated between the two patient groups, with AD patients showing poorer overall recall and more rapid forgetting of verbal information over delay. In addition, schizophrenia subjects showed a significantly greater deficit in visual confrontation naming than the AD group. The relationship of neuropsychological function and clinical symptoms of schizophrenia subjects was also examined. Results showed that word list learning, delayed recall, and rate of forgetting correlated most strongly with positive and negative symptoms. Recent neuropathological studies have indicated abnormalities in specific subfields of the hippocampal formation in schizophrenia that are also severely affected in AD. Though the specific histopathology of the two disorders differs, abnormalities in the common sites may underlie the common neuropsychological profile. [Copyright &y& Elsevier]