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• Common and distinct neural correlates are implicated in deception and false memory. • Both tasks activated the left superior frontal gyrus. • Deception relative to false memory activated frontoparietal and temporal regions. • fMRI could be useful for discriminating between deception and false memory. Previous research has highlighted the potential of fMRI in discriminating between truth and falsehood. However, falsehoods may not necessarily represent a deliberate intention to deceive; they can be a result of false memory too. It is important to show that fMRI can discriminate between deception and false memory, before it can be applied in legal contexts for deception detection. To this end, we performed a meta-analytic comparison of brain activation between deception and false memory. Activation likelihood estimation meta-analyses were conducted separately on 49 deception (61 contrasts; N total = 991) and 28 false memory (32 contrasts; N total = 484) studies. The contrasts obtained from these meta-analyses were entered into subsequent conjunction and contrast analyses. Deception and false memory tasks activated several frontoparietal regions. Both tasks activated the left superior frontal gyrus. Deception, relative to false memory, was associated with increased activation in the right superior temporal gyrus, right insula, left inferior parietal lobule and right superior frontal gyrus. These results provide some evidence to suggest that fMRI can discriminate between deception and false memory. [ABSTRACT FROM AUTHOR]

Objectives: Using a sample of dementia caregivers, we compared the diagnostic utility of the various short versions of the Zarit Burden Interview (ZBI) with the original scale to identify the most optimal one. Next, we established externally validated cutoffs for the various ZBI versions using probable depression cases as a reference standard. Methods: Caregivers (N = 394; 236 males; Agemean = 56 years) were administered the ZBI and a self-report depression measure. Participants who exceeded the cutoff for the latter were identified as probable depression cases. For each of the ZBI versions, a receiver operating characteristic (ROC) curve was plotted against probable depression cases. The area under these ROC curves between the short versions and the original were then compared using a non-parametric approach. Results: Compared to the original ZBI, the AUROC were similar for the 6-item, 7-item, and two 12-item versions, but significantly worse for the other short variants. The sensitivity and specificity of the cutoffs for all ZBI versions ranged from 77.3% to 85.2% and 60.1% to 79.8%, respectively. Conclusions: The original ZBI had good utility in identifying probable depression in caregivers, while the 6-item variant can be a useful alternative when short versions are preferred. [ABSTRACT FROM AUTHOR]

Abstract The improved Brazilian test is a popular method for indirectly measuring rock mechanical parameters, in which the current assumption of a uniform contact pressure distribution on the disc-jaw interface would result in measurement deviations because the real distribution is non-uniform. This investigation examines the influence of pressure distribution and friction on the determination of mechanical properties such as tensile strength σ t and Young's modulus E by both theoretical analyses and experiments. For a Brazilian disc under arbitrary distributions of normal and tangential loads, the power series expansion technique is used to find the analytical solutions of the full-field displacements and stresses. The related formulae for calculating the tensile strength σ t and Young's modulus E are derived. Eight load distributions with identical resultant forces are considered. The results show that the series solution converges in the form of a negative power law. Based on the Griffith failure criterion, the minimum contact angles that make the crack initiate at the center of the disc are given for different load distributions. The analysis indicates that these distributions have a significant influence on Young's modulus E and, if the contact angle is smaller, on tensile strength σ t. The deviation caused by ignoring friction is also discussed. The Brazilian test is implemented for shale disc samples. The tensile strength σ t and Young's modulus E of shale are determined indirectly using the theoretical formulae discussed here and experimental data. [ABSTRACT FROM AUTHOR]

Abstract The longitudinal decline in the integrity of several white matter (WM) tracts in behavioral variant frontotemporal dementia (bvFTD) has been documented. However, there is yet a clear relationship between this decline and that of executive function (EF), for the WM changes to meaningfully track progression in bvFTD. We sought to validate the use of diffusion tensor imaging (DTI) in tracking the progression of bvFTD with its associated decline in EF. Baseline and 1-year follow-up DTI scans were acquired from 23 patients with bvFTD and 26 healthy controls. EF composite score was derived via multiple tests. The longitudinal changes in DTI metrics were examined in both groups. Then, among patients (N = 18), we examined the associations between these changes and that of EF. Widespread WM alterations and decline in EF were observed only in patients. This EF decline was mostly associated with the disrupted integrity of the corpus callosum and anterior corona radiata. These longitudinal findings support the use of DTI in tracking the progression of bvFTD and its associated EF decline. Highlights • Widespread decline in white matter integrity was observed in bvFTD over a year • This decline in some frontal regions was linked to worsening executive function • These white matter changes can be used to track progression in bvFTD [ABSTRACT FROM AUTHOR]

Background: Previous cross-lagged studies on depression and memory impairment among the elderly have revealed conflicting findings relating to the direction of influence between depression and memory impairment. The current study aims to clarify this direction of influence by examining the cross-lagged relationships between memory impairment and depression in an Asian sample of elderly community dwellers, as well as synthesizing previous relevant cross-lagged findings via a meta-analysis. Methods: A total of 160 participants (Mage = 68.14, s.d. = 5.34) were assessed across two time points (average of 1.9 years apart) on measures of memory and depressive symptoms. The data were then fitted to a structural equation model to examine two cross-lagged effects (i.e. depressive symptoms→memory; memory→depressive symptoms). A total of 14 effect-sizes for each of the two cross-lagged directions were extracted from six studies (including the present; total N = 8324). These effects were then meta-analyzed using a three-level mixed effects model. Results: In the current sample, lower memory ability at baseline was associated with worse depressive symptoms levels at follow-up, after controlling for baseline depressive symptoms. However, the reverse effect was not significant; baseline depressive symptoms did not predict subsequent memory ability after controlling for baseline memory. The results of the meta-analysis revealed the same pattern of relationship between memory and depressive symptoms. Conclusions: These results provide robust evidence that the relationship between memory impairment and depressive symptoms is unidirectional; memory impairment predicts subsequent depressive symptoms but not vice-versa. The implications of these findings are discussed [ABSTRACT FROM AUTHOR]

Studies that examined white matter (WM) alterations in amnestic mild cognitive impairment (aMCI) abound. This timely meta-analysis aims to synthesize the results of these studies. Seventy-seven studies (total N aMCI = 1844) were included. Fourteen region-of-interest-based (ROI-based) (k ≥ 8; N aMCI ≥ 284 per ROI) and two activation likelihood estimation (ALE) meta-analyses (fractional anisotropy [FA]: k = 15; N aMCI = 463; mean diffusivity [MD]: k = 8; N aMCI = 193) were carried out. Among the many significant ROI-related findings, reliable FA and MD alterations in the fornix, uncinate fasciculus, and parahippocampal cingulum were observed in aMCI. Larger effects were observed in MD relative to FA. The ALE meta-analysis revealed a significant FA decrease among aMCI subjects in the posterior corona radiata. These results provide robust evidence of the presence of WM abnormalities in aMCI. Our findings also highlight the importance of carrying out both ROI-based and whole-brain-based research to obtain a complete picture of WM microstructural alterations associated with the condition.. [ABSTRACT FROM AUTHOR]

The present study utilized a person-centered approach to examine the different profiles of problem sleepers in a community sample of elderly. In addition, this study also explores how demographic and psychiatric variables may be related to these different profiles of sleep problems. A total of 515 participants (Mean age = 67 years, SD = 5) were administered self-report measures of sleep problems, depression and anxiety. Among them, 230 who reported significant problems in any of five selected sleep components were entered into a latent class analysis. The remaining 285 participants were assigned to a comparison control group. The profiles of ‘inadequate sleep', ‘disturbed sleep’, ‘trouble falling asleep’ and ‘multiple problems’ were identified. The ‘multiple problems’ group had significantly higher levels of depression and anxiety relative to the control group. Regression analyses indicated that these different profiles had contributed to a significant increase in variance explained in anxiety but not depression levels, on top of the severity of sleep problems and demographic variables. Although sleep problems occur among the elderly with considerable heterogeneity, they can generally be classified into four different profiles. Furthermore, the inclusion of sleep problem profiles can significantly enhance the prediction of anxiety symptoms. [ABSTRACT FROM AUTHOR]

Prior literature has suggested that cognitive flexibility is implicated in the feeling of hopelessness. However, studies on the nature of their relationship have been scarce. This study posits a moderation hypothesis on the relationship between cognitive flexibility and hopelessness. A total of 78 elderly participants (Mage = 70, SD = 6.1) were administered a self-report measure of hopelessness across two time points approximately 10 months apart and a measure of cognitive flexibility. We hypothesized that baseline hopelessness scores would moderate the relationship between cognitive flexibility and hopelessness scores 10 months later. Specifically, among the high baseline hopelessness group, we predicted that cognitively flexible participants would report lower hopelessness scores 10 months later. However, for the low baseline hopelessness group, cognitive flexibility would be unrelated to hopelessness scores 10 months later. The results of a bootstrapped moderation analysis controlling for age, sex, education, and general cognitive status supported our moderation hypothesis and predictions. These findings reveal the complex nature of the relationship between cognitive flexibility and hopelessness. The implications of these findings in the wider clinical context were discussed. [ABSTRACT FROM AUTHOR]

The relationship between depression, loneliness, and cognitive functioning among the elderly is not well understood in the literature. In the present study, we tested the moderating influence of depressive symptoms on loneliness and cognitive functioning. We recruited 100 community-dwelling older adults in Hong Kong. Demographic information, perceived loneliness, depressed mood, and general cognitive status were assessed. Results indicated that married participants reported lower levels of perceived loneliness (t(96) = 2.26,p = .03). We found a significant moderating effect of depressive symptoms on the relationship between perceived loneliness and general cognitive status (B = −.05,p = .002). Perceived loneliness correlated negatively with general cognitive status only in participants with higher levels of depressed mood (B = −.16,p = .01). Together, these findings suggest that perceived loneliness combined with depressed mood is related to poorer general cognitive status in older adults. The implications of these findings are discussed. [ABSTRACT FROM PUBLISHER]