The Development of Controlled Attention

The ability to maintain items of information within working memory is depending on the ability to allocate attention to items within WM. Individual differences in WM capacity may bedependent on the amount of information that can be held and maintained in the focus of attention. A basic question in cognitive development is whether individuals increase the capacity of the focus of attention or the efficiency with which they can process information. We examined the differences in typically developing children versus adults in the capacity and efficiency of attention control. In our study, children and young adults completed a dichotic attention switching task and their accuracy and response time was measured. Children’s accuracy on the attention switch tasks was not significantly different from adults’ accuracy. Children had significantly slower response time compared to the young adult group. The results of our study suggest that developmental changes in capacity of WM were not present for the task, but changes in processing speed and efficiency were critical cognitive mechanisms that influenced changes in inhibition from adolescence to adulthood. Our next step is to analyze neural processing data in order to assess developmental differences in the amount of cognitive energy required for both groups to perform these tasks

The Effects of Instruction on Landing Strategies in Female College-Aged Dancers and Non-Dancers: A Pilot Study

Background Female athletic participation has increased over the past decade and with it the prevalence of knee injuries. Current research demonstrates an increased risk of anterior cruciate ligament (ACL) injury for female athletes. However, a number of studies have pointed out that ballet and modern dancers exhibit a lower incidence of ACL injuries despite the fact that they perform jumping and landing frequently. Objective The objective of this study was to examine how dance experience and instruction affect the lower extremity biomechanics during drop landings. Specifically, lower extremity joint alignment and muscle activation of gluteus maximus and gluteus medius were assessed. Design Quasi-experimental, cross-sectional Methods Thirteen active women, 5 dancers and 8 non-dancers, 18-22 years of age, were recruited to participate in this study. In the non-instructed (NI) condition, participants were shown a video demonstrating the drop landing movement in a leg turned out (externally rotated) position. The participants performed the drop landing based on their interpretation of the movement on the video. They were then shown the same video with additional verbal instructions (VI) on how to perform the landing, and asked to perform the same drop landing again. Surface electromyography (EMG) was used to measure muscle activation of the gluteus medius and gluteus maximus during the landings. Kinematics of the lower extremity joints during the deceleration phase of landing were acquired using a digital motion capture system. 2x2 repeated measures ANOVA’s were used to assess the effect of dance experience (dancers and non-dancers) and verbal instruction (NI and VI) on lower extremity biomechanics and gluteal muscle activation. Results The 2-way ANOVA revealed a significant group by condition interaction with right gluteus medius (p=0.003) and right glut maximus (p=0.009). Dancers showed a significant increase in gluteus medius (p=0.02) while non-dancers showed a significant decrease in gluteus medius (p=0.04) with verbal instruction. Both groups showed significant changes in knee valgus (p\u3c0.001), hip abduction (p=0.027), and hip internal rotation (p=0.031) with verbal instruction. No significant differences were found when comparing those kinematic variables between groups. Discussion and Conclusion Our results demonstrated that brief verbal instruction has an effect on landing kinematics in college aged women. For both dancer and non-dancers, decreased knee valgus, decreased hip internal rotation, and increased hip abduction were found after verbal instruction was given. In addition, dancers exhibited increased gluteal muscle activation with instruction whereas non-dancers showed a decrease in gluteal muscle activation with instruction. Our findings indicated that explicit movement instruction may result in diminished muscle activation in non-dancers. The heightened awareness of neuromuscular control from dance training may be related to the reduced knee injury risk

Impairments in neurogenesis are not tightly linked to depressive behavior in a transgenic mouse model of Alzheimer\u27s disease.

Alzheimer\u27s disease (AD), the most common cause of dementia, is also associated with depression. Although the precise mechanisms that lead to depression in AD are unknown, the impairments in adult hippocampal neurogenesis observed in AD may play a role. Adult-born neurons play a critical role in regulating both cognition and mood, and reduced hippocampal neurogenesis is associated with depression in other neurological disorders. To assess the relationship between Alzheimer\u27s disease, neurogenesis, and depression, we studied human amyloid precursor protein (hAPP) transgenic mice, a well-characterized model of AD. We report that reductions in hippocampal neurogenesis are evident early in disease progression in hAPP mice, but a mild depressive phenotype manifests only in later stages of disease. We found that hAPP mice exhibited a reduction in BrdU-positive cells in the subgranular zone of the dentate gyrus in the hippocampus, as well as a reduction in doublecortin-expressing cells, relative to nontransgenic controls at 5-7 months of age. These alterations in neurogenesis appeared to worsen with age, as the magnitude of reduction in doublecortin-expressing cells was greater in hAPP mice at 13-15 months of age. Only 13-15 month old hAPP mice exhibited depressive behavior in the tail suspension test. However, mice at both age groups exhibited deficits in spatial memory, which was observed in the Morris water maze test for hippocampus-dependent memory. These findings indicate that neurogenesis impairments are accompanied by cognitive deficits, but are not tightly linked to depressive behavior in hAPP mice

ΔFosB Regulates Gene Expression and Cognitive Dysfunction in a Mouse Model of Alzheimer\u27s Disease.

Alzheimer\u27s disease (AD) is characterized by cognitive decline and 5- to 10-fold increased seizure incidence. How seizures contribute to cognitive decline in AD or other disorders is unclear. We show that spontaneous seizures increase expression of ΔFosB, a highly stable Fos-family transcription factor, in the hippocampus of an AD mouse model. ΔFosB suppressed expression of the immediate early gene c-Fos, which is critical for plasticity and cognition, by binding its promoter and triggering histone deacetylation. Acute histone deacetylase (HDAC) inhibition or inhibition of ΔFosB activity restored c-Fos induction and improved cognition in AD mice. Administration of seizure-inducing agents to nontransgenic mice also resulted in ΔFosB-mediated suppression of c-Fos, suggesting that this mechanism is not confined to AD mice. These results explain observations that c-Fos expression increases after acute neuronal activity but decreases with chronic activity. Moreover, these results indicate a general mechanism by which seizures contribute to persistent cognitive deficits, even during seizure-free periods

Epigenetic suppression of hippocampal calbindin-D28k by ΔFosB drives seizure-related cognitive deficits.

The calcium-binding protein calbindin-D28k is critical for hippocampal function and cognition, but its expression is markedly decreased in various neurological disorders associated with epileptiform activity and seizures. In Alzheimer\u27s disease (AD) and epilepsy, both of which are accompanied by recurrent seizures, the severity of cognitive deficits reflects the degree of calbindin reduction in the hippocampal dentate gyrus (DG). However, despite the importance of calbindin in both neuronal physiology and pathology, the regulatory mechanisms that control its expression in the hippocampus are poorly understood. Here we report an epigenetic mechanism through which seizures chronically suppress hippocampal calbindin expression and impair cognition. We demonstrate that ΔFosB, a highly stable transcription factor, is induced in the hippocampus in mouse models of AD and seizures, in which it binds and triggers histone deacetylation at the promoter of the calbindin gene (Calb1) and downregulates Calb1 transcription. Notably, increasing DG calbindin levels, either by direct virus-mediated expression or inhibition of ΔFosB signaling, improves spatial memory in a mouse model of AD. Moreover, levels of ΔFosB and calbindin expression are inversely related in the DG of individuals with temporal lobe epilepsy (TLE) or AD and correlate with performance on the Mini-Mental State Examination (MMSE). We propose that chronic suppression of calbindin by ΔFosB is one mechanism through which intermittent seizures drive persistent cognitive deficits in conditions accompanied by recurrent seizures

Health Status and Preventive Health Services Among Reproductive-Aged Women in Treatment for Opioid Use Disorder

OBJECTIVE: To assess the utilization of preventive health services and the prevalence of chronic health conditions among a cohort of women in treatment for opioid use disorder (OUD). METHODS: Ninety-seven women who were receiving treatment for OUD from a single urban treatment program completed a self-administered anonymous online questionnaire that asked about demographics, health, receipt of preventive health services, and utilization of health care. Descriptive statistics were used to describe data. RESULTS: More than one-third of respondents reported that their health was fair or poor, whereas one-quarter were very concerned with their health. Most participants (59%) reported at least one chronic health condition; nearly 1 in 5 reported two or more conditions. Less than half of respondents had received a routine medical examination in the past year. Vaccine uptake was low; 56% received the coronavirus disease 2019 vaccine and 36% received the annual influenza vaccine. CONCLUSIONS: Women in treatment for OUD could benefit from enhanced health care to address the high rates of chronic diseases and risk factors and underutilization of recommended preventive health services. Interventions and models of care that aim to enhance utilization of such services, and ultimately improve the health of this vulnerable population, may be worth exploring