"Do your eyes play tricks on you?” Asking older people about visual hallucinations in a general eye clinic

Visual hallucinations are well recognized in individuals with low vision and intact cognition (Charles Bonnet syndrome) (Teunisse et al., 1996). Visual hallucinations also occur in those with early manifestations of dementia with Lewy bodies (McKeith et al., 2005) and Parkinson's disease dementia (Williams and Lees, 2005). Typically, visual hallucinations in these conditions are complex recurrent hallucinations of people and animals and frequently reported as being unpleasant (Mosimann et al., 2006). Individuals with visual hallucinations are often reluctant to disclose details of their symptoms (Menon, 2005), but may instead report non-specific visual difficulties to their family physician or optometrist, resulting in referral to an eye clinic. Failure to elicit the presence of visual hallucinations may lead to inappropriate treatment of age-related ocular comorbidity, such as early catarac

Social networking sites and older users - a systematic review

Background: Social networking sites can be beneficial for senior citizens to promote social participation and to enhance intergenerational communication. Particularly for older adults with impaired mobility, social networking sites can help them to connect with family members and other active social networking users. The aim of this systematic review is to give an overview of existing scientific literature on social networking in older users. Methods: Computerized databases were searched and 105 articles were identified and screened using exclusion criteria. After exclusion of 87 articles, 18 articles were included, reviewed, classified, and the key findings were extracted. Common findings are identified and critically discussed and possible future research directions are outlined. Results: The main benefit of using social networking sites for older adults is to enter in an intergenerational communication with younger family members (children and grandchildren) that is appreciated by both sides. Identified barriers are privacy concerns, technical difficulties and the fact that current Web design does not take the needs of older users into account. Conclusions: Under the conditions that these problems are carefully addressed, social networking sites have the potential to support today's and tomorrow's communication between older and younger family member

Identifying Specific Interpretations and Use of Safety Behaviours in People with Distressing Visual Hallucinations: An Exploratory Study

Background: Visual hallucinations (VH) are a common experience and can be distressing and disabling, particularly for people suffering from psychotic illness. However, not everyone with visual hallucinations reports the experience to be distressing. Models of VH propose that appraisals of VH as a threat to wellbeing and the use of safety seeking behaviours help maintain the distress. Aims: This study investigated whether people with distressing VH report threat appraisals and use safety behaviours. Method: The study utilized a single group descriptive design, in which 15 participants with psychosis and VH were asked questions in order to assess the content, distress, appraisals, and behaviours associated with visual hallucinations. Results: People who found visual hallucinations distressing (n = 13) held negative appraisals about those hallucinations and specifically saw them as a threat to their physical or psychological wellbeing. They also engaged in safety seeking behaviours that were logically related to the appraisal and served to maintain the distress. Conclusions: People with distressing VH regard them as a threat to their wellbeing and use safety seeking behaviours as a result of this perceived threat. These key processes are potential targets for treatments that will alleviate the distress associated with V

Visual exploration in Parkinson's disease and Parkinson's disease dementia

Parkinson's disease, typically thought of as a movement disorder, is increasingly recognized as causing cognitive impairment and dementia. Eye movement abnormalities are also described, including impairment of rapid eye movements (saccades) and the fixations interspersed between them. Such movements are under the influence of cortical and subcortical networks commonly targeted by the neurodegeneration seen in Parkinson's disease and, as such, may provide a marker for cognitive decline. This study examined the error rates and visual exploration strategies of subjects with Parkinson's disease, with and without cognitive impairment, whilst performing a battery of visuo-cognitive tasks. Error rates were significantly higher in those Parkinson's disease groups with either mild cognitive impairment (P = 0.001) or dementia (P < 0.001), than in cognitively normal subjects with Parkinson's disease. When compared with cognitively normal subjects with Parkinson's disease, exploration strategy, as measured by a number of eye tracking variables, was least efficient in the dementia group but was also affected in those subjects with Parkinson's disease with mild cognitive impairment. When compared with control subjects and cognitively normal subjects with Parkinson's disease, saccade amplitudes were significantly reduced in the groups with mild cognitive impairment or dementia. Fixation duration was longer in all Parkinson's disease groups compared with healthy control subjects but was longest for cognitively impaired Parkinson's disease groups. The strongest predictor of average fixation duration was disease severity. Analysing only data from the most complex task, with the highest error rates, both cognitive impairment and disease severity contributed to a predictive model for fixation duration [F(2,76) = 12.52, P ≤ 0.001], but medication dose did not (r = 0.18, n = 78, P = 0.098, not significant). This study highlights the potential use of exploration strategy measures as a marker of cognitive decline in Parkinson's disease and reveals the efficiency by which fixations and saccades are deployed in the build-up to a cognitive response, rather than merely focusing on the outcome itself. The prolongation of fixation duration, present to a small but significant degree even in cognitively normal subjects with Parkinson's disease, suggests a disease-specific impact on the networks directing visual exploration, although the study also highlights the multi-factorial nature of changes in exploration and the significant impact of cognitive decline on efficiency of visual searc

PSYCHIATRY

www,elsevier.com/locate/psychre

A novel computer test to assess driving-relevant cognitive functions - a pilot study

ABSTRACT Background: The assessment of driving-relevant cognitive functions in older drivers is a difficult challenge as there is no clear-cut dividing line between normal cognition and impaired cognition and not all cognitive functions are equally important for driving. Methods: To support decision makers, the Bern Cognitive Screening Test (BCST) for older drivers was designed. It is a computer-assisted test battery assessing visuo-spatial attention, executive functions, eye-hand coordination, distance judgment, and speed regulation. Here we compare the performance in BCST with the performance in paper and pencil cognitive screening tests and the performance in the driving simulator testing of 41 safe drivers (without crash history) and 14 unsafe drivers (with crash history). Results: Safe drivers performed better than unsafe drivers in BCST (Mann-Whitney U test: U = 125.5; p = 0.001) and in the driving simulator (Student's t-test: t(44) = -2.64, p = 0.006). No clear group differences were found in paper and pencil screening tests (p > 0.05; ns). BCST was best at identifying older unsafe drivers (sensitivity 86%; specificity 61%) and was also better tolerated than the driving simulator test with fewer dropouts. Conclusions: BCST is more accurate than paper and pencil screening tests, and better tolerated than driving simulator testing when assessing driving-relevant cognition in older driver

Saccadic eye movement changes in Parkinson's disease dementia and dementia with Lewy bodies

Neurodegeneration in Parkinson's disease dementia (PDD) and dementia with Lewy bodies (DLB) affect cortical and subcortical networks involved in saccade generation. We therefore expected impairments in saccade performance in both disorders. In order to improve the pathophysiological understanding and to investigate the usefulness of saccades for differential diagnosis, saccades were tested in age- and education-matched patients with PDD (n = 20) and DLB (n = 20), Alzheimer's disease (n = 22) and Parkinson's disease (n = 24), and controls (n = 24). Reflexive (gap, overlap) and complex saccades (prediction, decision and antisaccade) were tested with electro-oculography. PDD and DLB patients had similar impairment in all tasks (P > 0.05, not significant). Compared with controls, they were impaired in both reflexive saccade execution (gap and overlap latencies, P 0.05). Patients with Parkinson's disease had, compared with controls, similar complex saccade performance (for all, P > 0.05) and only minimal impairment in reflexive tasks, i.e. hypometric gain in the gap task (P = 0.04). Impaired saccade execution in reflexive tasks allowed discrimination between DLB versus Alzheimer's disease (sensitivity ≥60%, specificity ≥77%) and between PDD versus Parkinson's disease (sensitivity ≥60%, specificity ≥88%) when ±1.5 standard deviations was used for group discrimination. We conclude that impairments in reflexive saccades may be helpful for differential diagnosis and are minimal when either cortical (Alzheimer's disease) or nigrostriatal neurodegeneration (Parkinson's disease) exists solely; however, they become prominent with combined cortical and subcortical neurodegeneration in PDD and DLB. The similarities in saccade performance in PDD and DLB underline the overlap between these conditions and underscore differences from Alzheimer's disease and Parkinson's diseas

Visual perception in Parkinson disease dementia and dementia with Lewy bodies

OBJECTIVE To quantify visual discrimination, space-motion, and object-form perception in patients with Parkinson disease dementia (PDD), dementia with Lewy bodies (DLB), and Alzheimer disease (AD). METHODS The authors used a cross-sectional study to compare three demented groups matched for overall dementia severity (PDD: n = 24; DLB: n = 20; AD: n = 23) and two age-, sex-, and education-matched control groups (PD: n = 24, normal controls [NC]: n = 25). RESULTS Visual perception was globally more impaired in PDD than in nondemented controls (NC, PD), but was not different from DLB. Compared to AD, PDD patients tended to perform worse in all perceptual scores. Visual perception of patients with PDD/DLB and visual hallucinations was significantly worse than in patients without hallucinations. CONCLUSIONS Parkinson disease dementia (PDD) is associated with profound visuoperceptual impairments similar to dementia with Lewy bodies (DLB) but different from Alzheimer disease. These findings are consistent with previous neuroimaging studies reporting hypoactivity in cortical areas involved in visual processing in PDD and DLB

Bitcoin and Its Position on Financial Markets

Import 22/07/2015Cílem této bakalářské práce je empiricky ověřit vliv finančních a makroekonomických ukazatelů na vývoj ceny Bitcoinu. Naplnění tohoto cíle je dosaženo pomocí vědeckých metod syntézy a deskriptivní a korelační analýzy. Důvodem pro ověřování byla skutečnost, že většina autorů prováděla svoji analýzu před téměř dvěma roky, což v případě Bitcoinu představuje dávnou minulost. Vliv konkrétních finančních a makroekonomických indikátorů na cenu Bitcoinu byl nejprve ověřen v dlouhém období, které vzniklo prodloužením původního období použitého v jiné předchozí práci. V tomto období byl potvrzen vztah mezi cenou Bitcoinu a hodnotou Dow Jones indexu. Nepotvrdila se předchozí koncepce závislosti mezi cenou Bitcoinu a hodnotou směnného kurzu USD/EUR, resp. cenou ropy. V tomto období byla rovněž objevena nepřímá závislost mezi cenou Bitcoinu a cenou zlata. V samostatné podkapitole byl pak ověřen vliv všech těchto veličin na cenu Bitcoinu v krátkém období.The aim of this bachelor thesis is to empirically check the influence of financial and macroeconomic indicators on Bitcoin price. This is achieved by using synthesis and descriptive and correlation analysis as the main scientific methods. The reason for the research was that the majority of authors have done their analysis almost two years ago, which in case of Bitcoin means a very long time. First, the influence of specific financial and macroeconomic indicators on Bitcoin price has been checked in the long run (a period that was created by prolonging the period used in previous literature). In this period the relationship between Bitcoin price and Dow Jones Index value has been confirmed. The previous concept of Bitcoin price and its dependence on USD/EUR exchange rate value and oil price respectively has not been confirmed. A negative correlation between Bitcoin price and gold price has been discovered. After that the influence of all these indicators on Bitcoin price has been checked for the short run as well.156 - Katedra národohospodářskávelmi dobř