Healthy Elderly Group Research Articles

Decrease of delta oscillatory responses is associated with increased age in healthy elderly

BackgroundThe purpose of this study was to investigate changes in delta event-related oscillations (EROs) in younger and older healthy elderly subjects. We hypothesized that delta EROs were affected by age-related changes, which could be reflected in a visual oddball paradigm. MethodThe study included two groups of subjects, 17 younger healthy elderly (mean age: 63.1±2.8years) and 17 gender- and education-matched older healthy elderly (mean age: 79.6±5.2years), who performed a visual oddball paradigm. EEG was recorded from F3, Fz, F4, C3, Cz, C4, P3, Pz, P4, O1, Oz and O2 locations. Peak-to-peak amplitudes of delta (0.5–3Hz) target ERO responses during the post-stimulus 0–800ms time window were measured. Repeated measures of ANOVA was used to analyze four locations (frontal, central, parietal, occipital), at three sagittal (left, midline, right) sites. Independent t-tests were applied for post-hoc analyses. ResultsThe older healthy elderly group had 16–25% lower values for the maximum peak-to-peak amplitudes of delta ERO compared with the younger healthy elderly group over frontal (p<0.003), central (p<0.0001) and parietal (p<0.007) locations [F3.96=4.396, p=0.015]. Furthermore, there was a moderate negative correlation between age and Cz peak-to-peak amplitude of target delta responses [r=−0.401, p<0.02], indicating the notion that peak-to-peak amplitude of Cz decreases as age increases. ConclusionIn the present study younger healthy elderly showed significantly higher event-related delta responses than older healthy elderly at frontal, central and parietal locations. Moreover, delta ERO responses decreased in accordance with age.

Comparison of physical function and activity in home-care patients with Parkinson's disease and healthy elderly people

Objective: To compare physical function and 24-h activity in home-care patients with Parkinson’s disease with those in healthy elderly people. Methods: Physical function (range of motion, muscle strength, activities of daily living, gait, and balance) was measured in 10 home-care patients with Parkinson’s disease (PD group) and 10 healthy elderly subjects (healthy group). As an indicator of the amount of physical activity per day, a triaxial accelerometer was used to measure the 24-h total impulse value; simultaneously, behavior recorders were used to measure 24-h posture. Results: The healthy group scored significantly higher in activities of daily living, walking speed, and balance. No significant difference was observed between groups in terms of range of motion, muscle strength, cadence, amount of physical activity per day, and number of postural changes. However, the PD group spent significantly more time per day standing and in a supine position. Conclusion: In the PD group, the amount of physical activity per day was comparable to that in the healthy elderly group, despite the decreased levels of activity caused by their impaired performance in activities of daily living. Range of motion and muscle strength may have been maintained by these patients’ self-training and by training at day-care centers. Our results suggest the importance of practicing postural transfers from the standing and supine positions and of intervention and guidance that aim to improve impaired performance in daily living. Hirosaki Med.J. 65:190―198,2014

Task-dependent Activity and Connectivity Predict Episodic Memory Network-based Responses to Brain Stimulation in Healthy Aging

BackgroundTranscranial magnetic stimulation (TMS) can affect episodic memory, one of the main cognitive hallmarks of aging, but the mechanisms of action remain unclear. ObjectivesTo evaluate the behavioral and functional impact of excitatory TMS in a group of healthy elders. MethodsWe applied a paradigm of repetitive TMS – intermittent theta-burst stimulation – over left inferior frontal gyrus in healthy elders (n = 24) and evaluated its impact on the performance of an episodic memory task with two levels of processing and the associated brain activity as captured by a pre and post fMRI scans. ResultsIn the post-TMS fMRI we found TMS-related activity increases in left prefrontal and cerebellum-occipital areas specifically during deep encoding but not during shallow encoding or at rest. Furthermore, we found a task-dependent change in connectivity during the encoding task between cerebellum-occipital areas and the TMS-targeted left inferior frontal region. This connectivity change correlated with the TMS effects over brain networks. ConclusionsThe results suggest that the aged brain responds to brain stimulation in a state-dependent manner as engaged by different tasks components and that TMS effect is related to inter-individual connectivity changes measures. These findings reveal fundamental insights into brain network dynamics in aging and the capacity to probe them with combined behavioral and stimulation approaches.

Usefulness of the simplified cough test in evaluating cough reflex sensitivity as a screening test for silent aspiration.

ObjectiveTo assess cough reflex sensitivity using the simplified cough test (SCT) and to evaluate the usefulness of SCT to screen for silent aspiration.MethodsThe healthy control group was divided into two subgroups: the young (n=29, 33.44±9.99 years) and the elderly (n=30, 63.66±4.37 years). The dysphagic elderly group (n=101, 72.95±9.19 years) consisted of patients with dysphagia, who suffered from a disease involving central nervous system (ischemic stroke 47, intracerebral hemorrhage 27, traumatic brain injury 11, encephalitis 5, hypoxic brain damage 3, and Parkinson disease 8). The SCT was performed using the mist of a 1% citric acid from a portable nebulizer. The time from the start of the inhalation to the first cough was measured as the cough latency. All the dysphagic patients underwent the videofluoroscopic swallowing study.ResultsThe cough latency was more significantly prolonged in the healthy elderly group than in the healthy young group (p<0.001), and in the dysphagic elderly group than in the healthy elderly group (p<0.001). The sensitivity and specificity of SCT were 73.8% and 72.5% for detecting aspiration in the dysphagic patients, and 87.1% and 66.7% for detecting silent aspiration in the aspirated patients.ConclusionCough latency measured with the SCT reflects the impairment of cough reflex in healthy elderly and dysphasic subjects. The results of this study show that the SCT test can be a valuable method of screening aspiration with or without cough in dysphasic patients.

Changes in the physical functions of pre-frail elderly women after participation in a 1-year preventative exercise program

The present study clarifies the effects of participation in a preventative health classroom program (exercise program) for 1 year on the physical functions of pre-frail elderly individuals in comparison with healthy elderly individuals. Participants in the study included 28 elderly pre-frail female participants and 28 elderly healthy female participants. Participants engaged in the exercise program for 1 year. There was no significant age or physical differences between both groups. Before and after the exercise program, the following physical function tests were carried out: grip strength, one-legged balance with eyes open, 5-m walking time and a timed up & go (TUG). The pre-frail elderly group tested significantly lower in the one-legged balance with eyes open test and the TUG test compared with the healthy elderly group. The 5-m walking time test improved significantly in both groups, but the TUG improved only in the pre-frail elderly group. Conversely, the grip strength and one-legged balance with eyes open tests remained unchanged. Improvements in the TUG and 5-m walking time tests were found in the pre-frail elderly group after the 1-year exercise program. Their results in the TUG test might be greater than those among the healthy elderly individuals.

Severity of sleep apnea syndrome is associated with arterial stiffness in elderly population

Obstructive sleep apnea (OSA) increases cardiovascular morbidity and mortality, and higher arterial stiffness is one of the biological markers for increased cardiovascular risk in OSA. However, with aging, several cardiovascular comorbidities and treatments may confound the relationship between OSA and arterial stiffness. Therefore, we sought to investigate the association between OSA and arterial stiffness in otherwise healthy elderly population. We performed a cross-sectional study of 476 elderly patients ( ⩾ 60 yr) recruited from community and the sleep clinic in a university hospital between November 2010 and January 2013. Clinical data were collected using a standardized protocol, including questions about current medical condition and its medication. OSA was diagnosed using laboratory polysomnography. Subjects were stratified into two groups according to the presence of comorbid medical conditions or its treatment, such as, hypertension, diabetes, and dyslipidemia. Each group was subdivided into three groups based on apnea-hypopnea index (AHI), consisting of normal (AHI < 15), mild-to-moderate OSA (15 ⩽ AHI ⩽ 30), and severe OSA (AHI > 30). Arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV) and cardio-ankle vascular index (CAVI). Among 476 participants, 101 subjects were without any comorbid medical condition or medication use. The baPWV, CAVI, CRP were significantly higher in patients with severe OSA group after adjustment for gender, body mass index and smoking status ( P = 0.003, 0.001, and 0.025 by ANCOVA, respectively) in healthy elderly group, but not in comorbid group. Multiple regression analysis showed baPWV, CAVI, and C-reactive protein had linear association with AHI ( β = 0.326, P = 0.002; β =0.326, P = 0.002; β = 3.253, P = 0.002, respectively) in healthy group. The severity of OSA is associated with arterial stiffness in otherwise healthy elderly individuals with OSA, but not in comorbid OSA individuals. In exploring the association between OSA and cardiovascular complications in the elderly, comorbidities need to be controlled, and we have found that OSA still increases cardiovascular risk in the elderly. This study was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (Grant No. 2010–0008886).

Elevated serum copper and ceruloplasmin levels in Alzheimer's disease

Copper takes part in a variety of biological reduction-oxidation (redox) processes, and is an important cofactor of many redox enzymes. Ceruloplasmin, the copper-transporting protein, also possesses an important redox capacity. We assessed serum copper, ceruloplasmin and free-copper levels in 89 patients with Alzheimer's disease (AD) (mean age, 77.83 years; 41 men, 48 women) and in 118 healthy individuals (mean age, 69.93 years; 50 men, 68 women). High (≥75th percentile), medium, and low (≤25th percentile) copper, ceruloplasmin and free-copper groups were classified according to their serum level. Serum copper (P = 0.026) and ceruloplasmin (P = 0.001) levels were significantly higher in the AD group than in the control group. There was no significant difference in serum free-copper levels between AD and healthy elderly groups (P = 0.975). After adjusting for age differences, serum copper (P = 0.049) was still significantly higher in the AD group. Furthermore, serum copper levels correlated with scores on the Boston naming test (r = -0.151, P = 0.037), indicating a close relationship between copper levels and cognitive abilities. The significant association between the copper concentration in peripheral serum and AD with elevated copper levels found in patients with AD is likely linked to the evolution of AD. Serum copper levels were significantly negatively correlated with scores on cognitive test subscores. AD patients may have significantly more "defective" ceruloplasmin, that is, apo-ceruloplasmin lacking its copper, than in healthy controls.

Temporal motor coordination in the ankle joint following upper motor neuron lesions.

[Purpose] We compared ankle temporal motor coordination between stroke, spinal disease and healthy elderly groups, and investigated the relationship between motor impairments and gait speed. [Subjects] Twenty-four patients with stroke, 19 post-operative spinal disease patients and 17 healthy elderly subjects participated. [Methods] Ankle temporal motor coordination of the three groups was assessed using the simple reaction time, the foot-tapping test, and a rhythm task. Rhythm error and rhythm variation were analyzed using the results of the rhythm task. Isometric muscle strength, spasticity, muscle stiffness, somatosensory and 10-m gait speed of the stroke and spinal disease subjects were also measured. [Results] Only the stroke group showed significant reductions in temporal accuracy and consistency in the rhythm task. Simple reaction time and the rhythm task were significantly poorer in the stroke group, whereas the foot-tapping test was not. Stepwise multiple regression analysis indicated gait speed was explained by rhythm error and plantarflexor strength in the stroke group, and rhythm error and simple reaction time in the spinal disease group. [Conclusion] Poor performance in simple reaction time and the rhythm task in the stroke group suggest these tasks are controlled by the supraspinal central nervous system. Negative features, particularly motor coordination, are more associated with gait speed than positive features.

Vero cell culture-derived pandemic influenza vaccines: preclinical and clinical development

Several subtypes of influenza A viruses with pandemic potential are endemic in bird populations throughout Asia, Africa and the Middle East, and evidence suggests that these viruses are adapting to the mammalian host. As emphasized by the high mortality rate of humans infected with H5N1 viruses, this situation presents a substantial risk to global human health. The Vero cell culture platform has been used to develop whole-virus influenza vaccines that provide broad cross-clade protection against viruses with pandemic potential, at low antigen doses, without the requirement for adjuvantation. The safety and immunogenicity of these vaccines has been demonstrated in studies with more than 10,000 individuals, including healthy adult and elderly subjects, children and various risk groups. These Vero cell-derived vaccines are licensed for prepandemic and pandemic use. The Vero platform is also being explored to develop next-generation live-attenuated and recombinant vaccines.

Probabilistic sequence learning in mild cognitive impairment

Mild Cognitive Impairment (MCI) causes slight but noticeable disruption in cognitive systems, primarily executive and memory functions. However, it is not clear if the development of sequence learning is affected by an impaired cognitive system and, if so, how. The goal of our study was to investigate the development of probabilistic sequence learning, from the initial acquisition to consolidation, in MCI and healthy elderly control groups. We used the Alternating Serial Reaction Time task (ASRT) to measure probabilistic sequence learning. Individuals with MCI showed weaker learning performance than the healthy elderly group. However, using the reaction times only from the second half of each learning block—after the reactivation phase—we found intact learning in MCI. Based on the assumption that the first part of each learning block is related to reactivation/recall processes, we suggest that these processes are affected in MCI. The 24-h offline period showed no effect on sequence-specific learning in either group but did on general skill learning: the healthy elderly group showed offline improvement in general reaction times while individuals with MCI did not. Our findings deepen our understanding regarding the underlying mechanisms and time course of sequence acquisition and consolidation.

Aging Decreases the Strength of Suprahyoid Muscles Involved in Swallowing Movements

Swallowing disorders are common in the elderly, and aging is a factor that affects swallowing function. The elevation of the hyoid bone is important for swallowing and is controlled by the suprahyoid muscles. The hyoid and laryngeal elevation allows the bolus to enter the esophagus. The suprahyoid muscles, therefore, play an important role in swallowing. The effects of aging on suprahyoid muscle strength are unclear. In this study, we analyzed the effects of aging on suprahyoid muscle strength by comparing the jaw opening functions of healthy adults and elderly adults. The subjects were 150 healthy volunteers consisting of 76 adults aged < 70 years (38 men and 38 women; mean age, 48.8 ± 13.8 years; range, 23-69) and 74 elderly adults aged > 70 years (37 men and 37 women; mean age, 78.1 ± 4.8 years; range, 70-92). The jaw opening force (JOF) was measured with a jaw opening sthenometer and compared between the healthy adult and elderly groups. The mean JOF of healthy adults was about 10 kg in men and about 6 kg in women, which was significantly greater than the mean JOF of the healthy elderly subjects (about 7 kg in men and about 4 kg in women). The JOF of the men was significantly greater than that of the women in the healthy adult and elderly groups. We thus propose that aging decreases the strength of suprahyoid muscles in healthy adults. The swallowing function may decrease even in healthy adults, aged over 70 years.

1591 – Different brain responses with matched performances between mild cognitive impairment and normal older adults during episodic retrieval: an erp study

Mild Cognitive Impairment (MCI) is a transitional stage from normal aging to dementia. The objective of this study was to determine whether a source retrieval ERP is an effective neural marker for differentiating MCI from normal older adults while their behavioral performances were matched which may have implications for identifying seniors at risk for cognitive decline. A source memory task was conducted on 16 aMCI and15 healthy older adults. Event-Related Potentials (ERPs) were recorded during retrieval phase. Memory performances were matched between the two groups by manipulating the number of items presented for each study session. The behavioral results showed that both source memory and item memory performances were perfectly matched between aMCI group under easy condition and healthy elderly group under hard condition. While under such case, the ERP results showed remarkable differences between the two groups. First, the right-lateralized positive-going old-new effects significantly decreased for aMCI group compared to control group, especially on the parietal sites. Second, the negative leftlateralized old new effect extended to the posterior sites of right hemisphere only in aMCI group but not in control group. The results showed that source retrieval ERP is an effective neural marker for differentiating MCI from normal older adults even when they have matched task performances. The results also suggested that MCI brain may involve more regions to compensate their reduced efficiency of dedicated circuits so that they could behave like normal older adults.

Proximal Tubule Function and Free Water Clearance: Comparison between Healthy Elderly and Young HIV+ Patients

In previous studies it was documented that proximal tubule sodium reabsorption capability was preserved in healthy elderly, while Thick Ascending Loop of Henle (TALH) one was reduced. Aim: Since, it has also been documented that senile changes are accelerated in HIV patients, we performed a prospective study in order to evaluate if there was a significant difference in proximal and TALH function between healthy elderly and HIV patients. Methods: Proximal and TALH was analyzed by performing hyposaline infusion test in 10 young (≥ 18-≤ 40 years old) HIV volunteers under treatment with tenofovir, free of viral charge, and normal renal function: serum creatinine, urinary sediment, and renal ultrasound), with the control group made up of 10 healthy old volunteers (≥ 65 years old). Results: During the test, it was observed that the HIV group had a significant reduction of natremia (HIV: 133 ± 1 mmol/l vs. healthy elderly: 139 ± 1 mmol/l, p=0.03), serum osmolarity (HIV: 276 ± 4 mOsm/l vs. elderly: 288 ± 3 mOsm/l, p=0.03) and free water clearance (HIV: 3.5 ± 3 ml/min/1.73 m² vs. elderly: 5 ± 8 ml/min/1.73 m², p ≤ 0.01). Besides, HIV patients showed an inadequate and significant increase in their urinary tonicity in comparison with the healthy elderly group: HIV: 170 ± 18 mOsm/l vs. elderly: 90 ± 10, p ≤ 0.01. Regarding proximal tubular function, it was found that it was preserved in both groups. Conclusion: Proximal tubule sodium reabsorption was normal, while free water clearance was significantly reduced in young HIV patients in comparison with healthy elderly volunteers.

Alterations in Balance and Gait Characteristics in Community-Dwelling Elderly Subjects Following Hemi Hip-Arthroplasty Compared to Healthy Control Subjects

The objective of this study was to identify changes in balance and deviations in gait following hemi hip arthroplasty in 52 community-dwelling elderly individuals (n = 21) compared to healthy elderly subjects (n = 31). We assessed the outcome measures of balance (Berg balance scale) and gait parameters (temporal, spatial, and walking velocity). Those who received a hemi hip arthroplasty demonstrated poor balance (37.857 ± 8.673) compared to healthy elderly (52.484 ± 2.096). During gait, right and left single-limb stance time did not show differences, but double limb support time and cadence had significant differences (P < 0.001) between the groups. Hemi hip arthroplasty elderly had shorter step length (25.055 ± 4.045 cm) and shorter stride length (49.583 ± 8.054 cm) compared to healthy elderly (36.212 ± 9.620 and 72.722 ± 21.036 cm, respectively). Step height was less in those who received a hemi hip arthroplasty thank in healthy elderly. Walking velocity for the hemi hip arthroplasty group (28.690 ± 7.406 cm/sec) was 48.99% less (P < 0.001) than that in the healthy elderly group (58.557 ± 19.210). Effects of exercise on balance and gait parameters for subjects with hemi hip arthroplasty were not significant. Body mass index did not influence the balance and gait parameters. Progressive aging does influence walking velocity between hemi hip arthroplasty and healthy elderly. In conclusion, community-dwelling elderly with hemi hip arthroplasty had poor balance and reduced gait parameters (i.e., double limb support time, cadence, step length, stride length, step height, and walking velocity) compared to age-matched healthy control subjects.

Association of Oral Health and Systemic Diseases in the Elderly

ABSTRACT Introduction Oral health may have an impact on general health with clinical implications. Objective To assess association of oral health with systemic diseases in the elderly. Materials and methods A cross-sectional study was conducted in 232 elderly subjects (above 50 years) who visited the geriatric medicine OPD at Government Medical College and Hospital, Chandigarh. Oral examination was conducted using the WHO Oral Assessment Form (1997). Written informed consent was taken. Patients were grouped according to their systemic health into six groups: Healthy elderly (group 1), hypertension and coronary artery disease (group 2), chronic obstructive pulmonary disease (group 3), diabetes (group 4), diabetes and hypertension (group 5) and hypertension (group 6). Results Average DMFT for coronal caries in the six groups was 23.8, 21.24, 22.15, 22.58, 17.83, 22.22 respectively and root caries 22.04, 18.05, 19.46, 14.90, 14.75, 18.62. Periodontal status was assessed by recording the CPI score and attachment loss. Chi-square test was applied, a significantly (p &lt; 0.05) higher CPI score was recorded for groups 2, 3, 6 compared to group 1 while attachment loss was significantly (p &lt; 0.05) higher in diabetics (group 4) compared to group 1. Applying the Z-test for proportions a significantly (p &lt; 0.05) higher number of group 1 edentulous subjects were using upper/lower complete dentures as compared to groups 4 and 5. Conclusion Findings of this study indicate an inverse relationship of periodontal health with systemic diseases in the selected sample but further research is needed with larger sample to authenticate the results. How to cite this article Talwar M, Malik G, Sharma S, Sachdev A, Chaudhry K. Association of Oral Health and Systemic Diseases in the Elderly. Int J Experiment Dent Sci 2013;2(1): 9-13.

Cognitive decline in elderly bipolar disorder patients: a follow‐up study

Older individuals with bipolar disorder may exhibit greater cognitive decline over time compared to mentally healthy elderly individuals. We aimed to investigate neurocognitive performance in bipolar disorder over a period of two years. A comprehensive neuropsychological test battery was applied at baseline and two years later to 65 euthymic elderly outpatients with bipolar disorder (mean age = 68.35, range: 60-90 years) and to a demographically comparable sample of 42 healthy elderly controls. A general linear model was used to measure changes over time for the two groups. The impact of baseline illness characteristics on intra-individual change in neurocognitive performance within the bipolar group was studied by using logistic regression analysis. At baseline and at follow up, bipolar disorder patients performed worse on all neurocognitive measures compared to the healthy elderly group. However, there was no significant group-by-time interaction between the bipolar disorder patients and the comparison group. Although older bipolar disorder patients have worse cognitive function than normal controls, they did not have greater cognitive decline over a period of two years.

SORL1 and SIRT1 mRNA expression and promoter methylation levels in aging and Alzheimer’s Disease

Alzheimer’s Disease (AD) is a neurodegenerative disorder and the most common cause of dementia among the elderly. Efforts have been made to understand the genetic and epigenetic mechanisms involved in the development of this disease. As SORL1 (sortilin-related receptor) and SIRT1 (sirtuin 1) genes have been linked to AD pathogenesis, we aimed to investigate their mRNA expression and promoter DNA methylation in post mortem brain tissues (entorhinal and auditory cortices and hippocampus) from healthy elderly subjects and AD patients. We also evaluated these levels in peripheral blood leukocytes from young, healthy elderly and AD patients, investigating whether there was an effect of age on these profiles. The comparative CT method by Real Time PCR and MALDI-TOF mass spectrometry were used to analyze gene expression and DNA methylation, respectively. SORL1 gene was differently expressed in the peripheral blood leukocytes and might act as a marker of aging in this tissue. Furthermore, we found that SORL1 promoter DNA methylation might act as one of the mechanisms responsible for the differences in expression observed between blood and brain for both healthy elderly and AD patients groups. The impact of these studied genes on AD pathogenesis remains to be better clarified.

Motor learning, retention and transfer after virtual-reality-based training in Parkinson's disease – effect of motor and cognitive demands of games: a longitudinal, controlled clinical study

ObjectivesTo evaluate the learning, retention and transfer of performance improvements after Nintendo Wii Fit™ training in patients with Parkinson's disease and healthy elderly people. DesignLongitudinal, controlled clinical study. ParticipantsSixteen patients with early-stage Parkinson's disease and 11 healthy elderly people. InterventionsWarm-up exercises and Wii Fit training that involved training motor (shifts centre of gravity and step alternation) and cognitive skills. A follow-up evaluative Wii Fit session was held 60 days after the end of training. Participants performed a functional reach test before and after training as a measure of learning transfer. Main outcome measuresLearning and retention were determined based on the scores of 10 Wii Fit games over eight sessions. Transfer of learning was assessed after training using the functional reach test. ResultsPatients with Parkinson's disease showed no deficit in learning or retention on seven of the 10 games, despite showing poorer performance on five games compared with the healthy elderly group. Patients with Parkinson's disease showed marked learning deficits on three other games, independent of poorer initial performance. This deficit appears to be associated with cognitive demands of the games which require decision-making, response inhibition, divided attention and working memory. Finally, patients with Parkinson's disease were able to transfer motor ability trained on the games to a similar untrained task. ConclusionsThe ability of patients with Parkinson's disease to learn, retain and transfer performance improvements after training on the Nintendo Wii Fit depends largely on the demands, particularly cognitive demands, of the games involved, reiterating the importance of game selection for rehabilitation purposes.

Dissociation between numerosity and duration processing in aging and early Parkinson's disease

Numerosity and duration processing have been shown to be underlain by a single representational mechanism, namely an accumulator, and to rely on a common cerebral network located principally in areas around the right intraparietal sulcus. However, recent neuropsychological findings reveal a dissociation between numerosity and duration processing, which suggests the existence of partially distinct mechanisms. In this study, we tested the idea of partially common and distinct mechanisms by investigating, for the first time, both numerical and temporal processing abilities in non-demented Parkinson's disease (PD) patients known to suffer from duration impairment and in healthy elderly adults known to have impaired performance in duration tasks. The aim was to assess whether this impaired duration processing would extend to numerosity processing. The participants had to compare either the numerosity of flashed dot sequences or the duration of single dot displays. The results demonstrate an effect of aging on duration comparison, healthy elderly participants making significantly more errors than healthy young participants. Importantly, the performance of PD patients on the duration task was worse than that of the healthy young and elderly groups, whereas no difference was found for numerosity comparison. This dissociation supports the idea that partly independent systems underlie the processing of numerosity and duration.

The desirable scale: Weighing social quality of assisted living facilities

Purpose In order to age-in-place, Dutch older adults have been housed in Assisted Living Facilities (ALFs) for over 25 years. Here they live independently but can rely on services and care facilities. The size of these ALFs ranges from 30 up to 300 residents. They are often considered to be outdated. Nevertheless, they continue to be built but their character is changing by housing a greater mix of people. In contrast with the field of housing and care for dementia, the impact of scale on social quality of housing has not yet been explored. This paper discusses the relationship between scale, social interaction, the facilities offered to the tenants, and the perceived quality of living conditions. Method We reviewed the literature on concepts of scale, mix of functions and groups, and quality of social environment of housing for the elderly. After this desk research, a strategic selection was made from the database of the Expertise Centre Housing-Care. This paper presents the results from the multiple case study of the selected 24 projects. Observations were made on each of them. Around 196 inhabitants, 48 initiators, and 48 professionals were interviewed using a narrative method, qualitatively analysed in ATLAS ti. Results & Discussion The projects were far more mixed than presumed, resulting in two contra-dictory findings: a positive influence on social interaction and informal care but a negative influence on perceptions of confronting a more care-demanding future. Government and initiators intentionally presume informal care: healthy elderly support other groups. This is directly related to the mix of the independency among inhabitants. Where present, this mix encourages social interaction and quality. However, due to reductions by government and changing demands for hous-ing, more people can age at home. This results in more limited mutual informal care and so undermines the concept of Assisted Living Facilities. Depending on the situating, scale influences this precarious balance directly: small-scale pro-jects are more appreciated in villages, large-scale projects in cities. Safety experience -an important social quality of housing- is better assured at small scale. Regarding social interaction, in villages there is more informal contact and social cohesion; this social control has both positive and negative effects. In city environments however, the lack of the negative aspects of social control are a major factor in appreciating the large scale. Moreover, a good mix of people is more easily obtained in a large scale setting: diversity, liveliness, and activity are all more appreciated in cities. Ulti-mately, aggression within social relations has a strong negative influence on social activity and bonding: elderly avoid communal activities within the ALFs. The influence of scale on relational aggression will be analysed in the final phase of this research during the first half year of 2012.