Sima Salarirad

Brain lesions, hypertension and cognitive ageing in the 1921 and 1936 Aberdeen birth cohorts

The objectives of this study are to model the relative effects of positive (childhood intelligence) and negative (magnetic resonance imaging (MRI)-derived white matter hyperintensities (WMH)) predictors of late-life intelligence in two well-characterised normal cohorts aged 68 and 78 and to measure the influence of hypertension on WMH and lifelong cognitive change. The Scottish Mental Surveys of 1932 and 1947 tested the intelligence of almost all school children at age 11. One hundred and one participants born in 1921 and 233 participants born in 1936 had brain MRI, with measurement of WMH using Scheltens‘ scale, and tests of late-life fluid intelligence. Structural equation models of the effect of childhood intelligence and brain WMH on the general intelligence factor ‘g’ in late life in the two samples were constructed using AMOS 18. Similar models were constructed to test the effect of hypertension on WMH and lifelong cognitive change. Fluid intelligence scores were lower and WMH scores were higher in the older samples. Hypertensive participants in both samples had more WMH than normotensive participants. The positive influence of childhood intelligence on ‘g’ was greater in the younger sample. The negative effect of WMH on ‘g’ was linear and greater in the older sample due to greater WMH burden. The negative effect of hypertension on lifelong cognitive ageing was all mediated via MRI-derived brain WMH. The positive relationship between childhood and late-life intelligence decreases with age. The negative relationship between WMH and late-life intelligence is linear and increases with age.

Brain Volume and Survival from Age 78 to 85: The Contribution of Alzheimer-Type Magnetic Resonance Imaging Findings

OBJECTIVES: To test the prediction of survival using magnetic resonance imaging (MRI)–derived global and regional brain volumes in subjects aged 78 to 79 without dementia.

Early life socioeconomic circumstance and late life brain hyperintensities--a population based cohort study.

Context There have been many reports confirming the association between lower childhood socioeconomic circumstance and cardiovascular disease but evidence for links with cerebrovascular disease is contradictory. Hyperintensities on brain magnetic resonance imaging are associated with vascular risk factors, cognitive decline, dementia and death. However, the relationship between childhood socioeconomic circumstance and these lesions is unclear. Objective To test the hypothesis that childhood socioeconomic circumstance is associated with late life hyperintensity burden and that neither adult socioeconomic circumstance nor change in socioeconomic circumstance during life influence this effect. Design Cohort study Setting Community Participants 227 community dwelling members of the 1936 Aberdeen Birth Cohort aged 68 years, who were free from dementia. Main Outcome Measures Relationship between early life socioeconomic circumstance (paternal occupation) and abundance of late life brain hyperintensities. Results We find significant negative correlations between childhood socioeconomic circumstance and white matter hyperintensities (ρ = −0.18, P<0.01), and periventricular hyperintensities (ρ = −0.15, P<0.05), between educational attainment and white matter hyperintensities (ρ = −0.15, P<0.05) and periventricular hyperintensities (ρ = −0.17, P<0.05), and between childhood intelligence and periventricular hyperintensities (ρ = −0.14, P<0.05). The relationship is strongest for childhood socioeconomic circumstance and regional white matter hyperintensities, where there is a step change in increased burden from paternal occupation grades equivalent to a shift from “white collar” to “blue collar” paternal occupation. Significant correlations were also found between hypertension and hyperintensity burden in all brain regions (ρ = 0.15–0.24, P<0.05). In models that include hypertension, the magnitude of the effect of childhood socioeconomic circumstance is similar to and independent from that of hypertension. Conclusions Childhood socioeconomic circumstance predicts the burden of brain white matter hyperintensities aged 68 years. The mechanism underlying this effect is unknown, but may act through fetal and/or early life programming of cerebrovascular disease. Future work to understand this vulnerability will inform strategies to reduce dementia and stroke.

Depressive symptoms in late life and cerebrovascular disease: the importance of intelligence and lesion location.

The influence of white matter lesions on depressive symptoms in healthy ageing populations remains unclear. In this study, we examined the relationship between depressive symptoms and magnetic resonance imaging (MRI) detected cerebrovascular disease in a normal population living independently in the community, and measured the influence of location of brain abnormalities, fluid intelligence, living alone, and sex.

Therapeutic effects of 10-HzPulsed wave lasers in rat depression model: A comparison between near-infrared and red wavelengths

The application of transcranial low‐level light/laser therapy (tLLLT) in the range of red to near‐infrared (NIR) spectrum for psychological disorders is a new area that is attracting growing interest in recent years. The photomodulation effects of NIR and red coherent lights on the activity of cytochrome c oxidase in neuronal cells of brain have been recently introduced. This study, therefore, sought to compare the therapeutic effects of 10‐Hz pulsed wave NIR (810 nm) laser with red (630 nm) laser using the same delivered energy density and Citalopram in rat chronic mild stress (CMS) model of depression and anxiety.

Brain hyperintensity location determines outcome in the triad of impaired cognition, physical health and depressive symptoms: A cohort study in late life.

PURPOSE OF THE STUDY Brain hyperintensities, detectable with MRI, increase with age. They are associated with a triad of impairment in cognitive ability, depression and physical health. Here we test the hypothesis that the association between hyperintensities and cognitive ability, physical health and depressive symptoms depends on lesion location. DESIGN AND METHODS 244 members of the Aberdeen 1936 Birth Cohort were recruited to this study. 227 participants completed brain MRI and their hyperintensities were scored using Scheltenss scale. 205 had complete imaging, cognitive, physical health and depressive symptom score data. The relationships between hyperintensity location and depressive symptoms, cognitive ability and physical health were examined by correlation and structural equation analysis. RESULTS We found that depressive symptoms correlated with hyperintensity burden in the grey matter (r=0.14, p=0.04) and infratentorial regions (r=0.17, p=0.01). Infratentorial hyperintensities correlated with reduced peak expiratory flow rate (r=-0.26, p<0.001) and impaired gait (r=0.13, p=0.05). No relationship was found between white matter and periventricular (supratentoral) hyperintensities and depressive symptoms. Hyperintensities in the supratentorial and infratentorial regions were associated with reduced cognitive performance. Using structural equation modelling we found that the association between hyperintensities and depressive symptoms was mediated by negative effects on physical health and cognitive ability. CONCLUSIONS Hyperintensities in deep brain structures are associated with depressive symptoms, mediated via impaired physical health and cognitive ability. Participants with higher cognitive ability and better physical health are at lower risk of depressive symptoms.

A comparison between antidepressant effects of transcranial near-infrared laser and citalopram in a rat model of depression

Depression is a common psychiatric disorder that its prevalence has been reported to be 16% among adults. In recent years, transcranial near-infrared laser therapy (NILT) has gained considerable attention as a novel non-pharmaceutical method for depression. The present study was designed to compare the efficacy of two different treatment strategies in a rat model of depression. Forty male Wistar rats (180-200 g) divided into 4 groups: control, depressive, depressive-NILT, and depressive-Citalopram. All animals excepted control group was exposed to chronic mild stress (CMS) for 4 weeks. Rats in laser group received 10-Hz pulsed NILT (810 nm, energy density 1.2 J/cm2 per session) transcranially for a total of 12 sessions over a three-week period. Citalopram (10 mg/kg, Intraperitoneal) was administered for 21 consecutive days. Depressive-like behavior was tested in the forced swimming test (FST) model. Serum cortisol levels were also determined. The results of FST showed an increase in swimming and decrease in immobility period, for both NILT and Citalopram groups compared to the stress group. There was also no significant difference between the experimental groups in climbing behavior. The induction of CMS significantly increased serum cortisol levels and treatments with NILT and Citalopram decreased it. Our findings showed that NILT will be more beneficial to improve the depressive-like behaviors in the rat. Our data also showed that transcranial NILT was as effective as Citalopram in the treatment of depression. Therefore, these pieces of evidence may help improve NILT as an alternative non-pharmaceutical method for depression therapy.

Depressive symptoms in late life and cerebrovascular disease

The influence of white matter lesions on depressive symptoms in healthy ageing populations remains unclear. In this study, we examined the relationship between depressive symptoms and magnetic resonance imaging (MRI) detected cerebrovascular disease in a normal population living independently in the community, and measured the influence of location of brain abnormalities, fluid intelligence, living alone, and sex.

DEPRESSIVE SYMPTOMS IN LATE LIFE AND CEREBROVASCULAR DISEASE: THE IMPORTANCE OF INTELLIGENCE AND LESION LOCATION: Research Article: Depressive Symptoms and Cerebrovascular Disease

The influence of white matter lesions on depressive symptoms in healthy ageing populations remains unclear. In this study, we examined the relationship between depressive symptoms and magnetic resonance imaging (MRI) detected cerebrovascular disease in a normal population living independently in the community, and measured the influence of location of brain abnormalities, fluid intelligence, living alone, and sex.

A comparison of MRI derived vascular burden and hippocampal volumes in healthy ageing and Alzheimer's disease

Figure 1. Multiple regression inSPM5between resting state hippocampal functional connectivity and (a) autobiographical memory score in the whole cortex, (b) flexibility abilities (responce time in seconds) within the DMN. The results are shown at p FDR corrected<.05, correcting for gender and education level. Plots illustrate the correlations between hippocampal connectivity in the peak voxel of the regression and neuropsychological performances.