Browsing by Subject "Memory"
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Item Acute and long-term effects of Δ9-tetrahydrocannabinol on object recognition and anxiety-like activity are age- and strain-dependent in mice(Elsevier, 2017-12) Kasten, C.R.; Zhang, Y.; Boehm II, S.L.; Psychology, School of ScienceUse of exogenous cannabinoids disrupts the fine-tuned endocannabinoid receptor system, possibly leading to alterations in cognition, memory, and emotional processes that endure long after cannabinoid use has stopped. Long-term adolescent use may uniquely disrupt these behaviors when compared to adult use. The current study explored the acute and long-term behavioral effects of six 10mg/kg Δ9-tetrahydrocannabinol (THC) injections across the adolescent or early adult period in male inbred C57Bl/6J and DBA/2J mice. The acute and prolonged effects of THC on object memory using the novel object recognition task, unconditioned anxiety in the elevated plus maze and open field, and sedative effects in the open field were examined. Acute THC treatment resulted in anxiogenic activity in both strains, but only caused sedation in B6 mice. Repeated THC treatment resulted in a protracted effect on object recognition, but not unconditioned anxiety, assessed 4weeks later. In both strains, an adolescent history of THC treatment disrupted later object recognition. Interestingly, in B6 mice an adult history of THC exposure appeared to rescue a deficit in object recognition observed in vehicle-treated adults. Repeated THC administration also produced a protracted effected on CB1R protein expression. Animals treated with THC in adolescence maintained increased levels of CB1R protein expression compared to their adult THC-treated counterparts at five weeks following the last injection. These results indicate that THC use may have long-lasting effects with adolescence being a unique period of susceptibility.Item Adult neurogenesis and neurodegenerative diseases: A systems biology perspective(Wiley, 2017-01) Horgusluoglu, Emrin; Nudelman, Kelly; Nho, Kwangsik; Saykin, Andrew J.; Medical and Molecular Genetics, School of MedicineNew neurons are generated throughout adulthood in two regions of the brain, the olfactory bulb and dentate gyrus of the hippocampus, and are incorporated into the hippocampal network circuitry; disruption of this process has been postulated to contribute to neurodegenerative diseases including Alzheimer's disease and Parkinson's disease. Known modulators of adult neurogenesis include signal transduction pathways, the vascular and immune systems, metabolic factors, and epigenetic regulation. Multiple intrinsic and extrinsic factors such as neurotrophic factors, transcription factors, and cell cycle regulators control neural stem cell proliferation, maintenance in the adult neurogenic niche, and differentiation into mature neurons; these factors act in networks of signaling molecules that influence each other during construction and maintenance of neural circuits, and in turn contribute to learning and memory. The immune system and vascular system are necessary for neuronal formation and neural stem cell fate determination. Inflammatory cytokines regulate adult neurogenesis in response to immune system activation, whereas the vasculature regulates the neural stem cell niche. Vasculature, immune/support cell populations (microglia/astrocytes), adhesion molecules, growth factors, and the extracellular matrix also provide a homing environment for neural stem cells. Epigenetic changes during hippocampal neurogenesis also impact memory and learning. Some genetic variations in neurogenesis related genes may play important roles in the alteration of neural stem cells differentiation into new born neurons during adult neurogenesis, with important therapeutic implications. In this review, we discuss mechanisms of and interactions between these modulators of adult neurogenesis, as well as implications for neurodegenerative disease and current therapeutic research.Item Alpha-synuclein (SNCA) polymorphisms exert protective effects on memory after mild traumatic brain injury(Elsevier, 2016-09-06) Shee, Kevin; Lucas, Alexandra; Flashman, Laura A.; Nho, Kwangsik; Tsongalis, Gregory J.; McDonald, Brenna C.; Saykin, Andrew J.; McAllister, Thomas W.; Rhodes, C. Harker; Psychiatry, School of MedicineProblems with attention and short-term learning and memory are commonly reported after mild traumatic brain injury (mTBI). Due to the known relationships between α-synuclein (SNCA), dopaminergic transmission, and neurologic deficits, we hypothesized that SNCA polymorphisms might be associated with cognitive outcome after mTBI. A cohort of 91 mTBI patients one month after injury and 86 healthy controls completed a series of cognitive tests assessing baseline intellectual function, attentional function, and memory, and was genotyped at 13 common single nucleotide polymorphisms (SNPs) in the SNCA gene. Significant differences in two memory measures (p = 0.001 and 0.002), but not baseline intellectual function or attentional function tasks, were found between the mTBI group and controls. A highly significant protective association between memory performance and SNCA promoter SNP rs1372525 was observed in the mTBI patients (p = 0.006 and 0.029 for the long and short delay conditions of the California Verbal Learning Tests, respectively), where the presence of at least one copy of the A (minor) allele was protective after mTBI. These results may help elucidate the pathophysiology of cognitive alterations after mTBI, and thus warrant further investigation.Item Amantadine Did Not Positively Impact Cognition in Chronic Traumatic Brain Injury: A Multi-Site, Randomized, Controlled Trial(Mary Ann Liebert, 2018-10-01) Hammond, Flora M.; Sherer, Mark; Malec, James F.; Zafonte, Ross D.; Dikmen, Sureyya; Bogner, Jennifer; Bell, Kathleen R.; Barber, Jason; Temkin, Nancy; Physical Medicine and Rehabilitation, School of MedicineDespite limited evidence to support the use of amantadine to enhance cognitive function after traumatic brain injury (TBI), the clinical use for this purpose is highly prevalent and is often based on inferred belief systems. The aim of this study was to assess effect of amantadine on cognition among individuals with a history of TBI and behavioral disturbance using a parallel-group, randomized, double-blind, placebo-controlled trial of amantadine 100 mg twice-daily versus placebo for 60 days. Included in the study were 119 individuals with two or more neuropsychological measures greater than 1 standard deviation below normative means from a larger study of 168 individuals with chronic TBI (>6 months post-injury) and irritability. Cognitive function was measured at treatment days 0, 28, and 60 with a battery of neuropsychological tests. Composite indices were generated: General Cognitive Index (included all measures), a Learning Memory Index (learning/memory measures), and Attention/Processing Speed Index (attention and executive function measures). Repeated-measures analysis of variance revealed statistically significant between-group differences favoring the placebo group at day 28 for General Cognitive Index (p = 0.002) and Learning Memory Index (p = 0.001), but not Attention/Processing Speed Index (p = 0.25), whereas no statistically significant between-group differences were found at day 60. There were no statistically significant between-group differences on adverse events. Cognitive function in individuals with chronic TBI is not improved by amantadine 100 mg twice-daily. In the first 28 days of use, amantadine may impede cognitive processing. However, the effect size was small and mean scores for both groups were generally within expectations for persons with history of complicated mild-to-severe TBI, suggesting that changes observed across assessments may not have functional significance. The use of amantadine to enhance cognitive function is not supported by these findings.Item Assessing and validating reliable change across ADNI protocols(Taylor & Francis, 2022) Hammers, Dustin B.; Kostadinova, Ralitsa; Unverzagt, Frederick W.; Apostolova, Liana G.; Alzheimer’s Disease Neuroimaging Initiative; Neurology, School of MedicineObjective: Reliable change methods can aid in determining whether changes in cognitive performance over time are meaningful. The current study sought to develop and cross-validate 12-month standardized regression-based (SRB) equations for the neuropsychological measures commonly administered in the Alzheimer's Disease Neuroimaging Initiative (ADNI) longitudinal study. Method: Prediction algorithms were developed using baseline score, retest interval, the presence/absence of a 6-month evaluation, age, education, sex, and ethnicity in two different samples (n = 192 each) of robustly cognitively intact community-dwelling older adults from ADNI - matched for demographic and testing factors. The developed formulae for each sample were then applied to one of the samples to determine goodness-of-fit and appropriateness of combining samples for a single set of SRB equations. Results: Minimal differences were seen between Observed 12-month and Predicted 12-month scores on most neuropsychological tests from ADNI, and when compared across samples the resultant Predicted 12-month scores were highly correlated. As a result, samples were combined and SRB prediction equations were successfully developed for each of the measures. Conclusions: Establishing cross-validation for these SRB prediction equations provides initial support of their use to detect meaningful change in the ADNI sample, and provides the basis for future research with clinical samples to evaluate potential clinical utility. While some caution should be considered for measuring true cognitive change over time - particularly in clinical samples - when using these prediction equations given the relatively lower coefficients of stability observed, use of these SRBs reflects an improvement over current practice in ADNI.Item Associations between Cortical Thickness and Metamemory in Alzheimer’s Disease(Springer, 2022) Duran, Tugce; Woo, Ellen; Otero, Diana; Risacher, Shannon L.; Stage, Eddie; Sanjay, Apoorva B.; Nho, Kwangsik; West, John D.; Phillips, Meredith L.; Goukasian, Naira; Hwang, Kristy S.; Apostolova, Liana G.; Neurology, School of MedicineMetacognitive deficits affect Alzheimer's disease (AD) patient safety and increase caregiver burden. The brain areas that support metacognition are not well understood. 112 participants from the Imaging and Genetic Biomarkers for AD (ImaGene) study underwent comprehensive cognitive testing and brain magnetic resonance imaging. A performance-prediction paradigm was used to evaluate metacognitive abilities for California Verbal Learning Test-II learning (CVLT-II 1-5) and delayed recall (CVLT-II DR); Visual Reproduction-I immediate recall (VR-I Copy) and Visual Reproduction-II delayed recall (VR-II DR); Rey-Osterrieth Complex Figure Copy (Rey-O Copy) and delayed recall (Rey-O DR). Vertex-wise multivariable regression of cortical thickness was performed using metacognitive scores as predictors while controlling for age, sex, education, and intracranial volume. Subjects who overestimated CVLT-II DR in prediction showed cortical atrophy, most pronounced in the bilateral temporal and left greater than right (L > R) frontal cortices. Overestimation of CVLT-II 1-5 prediction and DR performance in postdiction showed L > R associations with medial, inferior and lateral temporal and left posterior cingulate cortical atrophy. Overconfident prediction of VR-I Copy performance was associated with right greater than left medial, inferior and lateral temporal, lateral parietal, anterior and posterior cingulate and lateral frontal cortical atrophy. Underestimation of Rey-O Copy performance in prediction was associated with atrophy localizing to the temporal and cingulate areas, and in postdiction, with diffuse cortical atrophy. Impaired metacognition was associated to cortical atrophy. Our results indicate that poor insight into one's cognitive abilities is a pervasive neurodegenerative feature associated with AD across the cognitive spectrum.Item Autobiographical Memory Function as a Related Factor to Resilience of Older Adults(2023-05-25) Park, Sangmi; Lee, Chang Dae; Kim, Jung-Ran; Kim, Tae Hui; Park, Ji-HyukPurpose: This study aimed to measure the autobiographical memory function (AMF) of community-dwelling older adults to analyze its association with reminiscence function and with resilience. Methods: A survey was conducted on cognitively and psychologically healthy older adults aged 60 years and older living in the community. The Korean Version of Thinking About Life Experiences, Connor-Davidson Resilience Scale, and Reminiscence Functions Scale for the Elderly were used to measure AMF, resilience, and reminiscence function, respectively. Pearson correlation analysis and hierarchical regression analysis were conducted to examine the associations between variables. Results: The mean age of the participants was 73.14 years (SD = 7.59) (n = 121). The mean score of AMF was 1.99 (SD = 0.72). AMF tended to decrease with age (p = .32). AMFs were positively associated with reminiscence functions (p < .001). After controlling for sociodemographic and health characteristics, AMF was positively associated with resilience (β = 0.229, p < .05). AMF explained 4.2% of the variance in resilience. Conclusion: The study confirmed that AMF is a related factor to the resilience of older adults. Further studies are recommended to measure AMF with various samples, including older adults with depression and cognitive decline, and to analyze it’s association with health-related variables in order to support the advantage of AMF in older adults’ health.Item Cognitive complaints in older adults at risk for Alzheimer's disease are associated with altered resting-state networks(Elsevier, 2016-12-22) Contreras, Joey A.; Goni, Joaquin; Risacher, Shannon L.; Amico, Enrico; Yoder, Karmen; Dzemidzic, Mario; West, John D.; McDonald, Brenna C.; Farlow, Martin R.; Sporns, Olaf; Saykin, Andrew J.; Department of Radiology and Imaging Sciences, IU School of MedicineINTRODUCTION: Pathophysiological changes that accompany early clinical symptoms in prodromal Alzheimer's disease (AD) may have a disruptive influence on brain networks. We investigated resting-state functional magnetic resonance imaging (rsfMRI), combined with brain connectomics, to assess changes in whole-brain functional connectivity (FC) in relation to neurocognitive variables. METHODS: Participants included 58 older adults who underwent rsfMRI. Individual FC matrices were computed based on a 278-region parcellation. FastICA decomposition was performed on a matrix combining all subjects' FC. Each FC pattern was then used as a response in a multilinear regression model including neurocognitive variables associated with AD (cognitive complaint index [CCI] scores from self and informant, an episodic memory score, and an executive function score). RESULTS: Three connectivity independent component analysis (connICA) components (RSN, VIS, and FP-DMN FC patterns) associated with neurocognitive variables were identified based on prespecified criteria. RSN-pattern, characterized by increased FC within all resting-state networks, was negatively associated with self CCI. VIS-pattern, characterized by an increase in visual resting-state network, was negatively associated with CCI self or informant scores. FP-DMN-pattern, characterized by an increased interaction of frontoparietal and default mode networks (DMN), was positively associated with verbal episodic memory. DISCUSSION: Specific patterns of FC were differently associated with neurocognitive variables thought to change early in the course of AD. An integrative connectomics approach relating cognition to changes in FC may help identify preclinical and early prodromal stages of AD and help elucidate the complex relationship between subjective and objective indices of cognitive decline and differences in brain functional organization.Item Connectedness of Existence(2014) Ingram, Margaret Elizabeth; Setser, MeredithI am drawn to the most human of things, the ordinary everyday experiences that connect us. I seek to remember pieces of life that are easily forgotten or left behind. It is within the constructs of interdependence that my work explores the poetic space of a shared human experience. These connections are made evident through the suggestion of memory, identity and the idea of the viewer as collaborator. I seek to create a narrative in which the viewer becomes aware of change and discovery within the behavior of an individual self. In my most recent work, the idea of the viewer has visually and metaphorically manifested into the act of drawing a circle. The shape of the circle is meant to be representative of the nature of experience within the intricacies of both the enlightened mind as well as the confused mind. It is a mutual circle or a circle of togetherness where the connectedness of our existence becomes indisputable. The circle in the beginning and ending, presence and absence. The viewer, then, becomes a silent collaborator who quietly charges my work as I search for social understanding of both the viewer and myself. In this way the viewer becomes a willing participant as well as the subject.Item Contradiction: Permanent Temporal(2016) Li, Shuyu; Hudnall, KatieEach individual utilizes memory and experience as the path to explore unknown, and memory functions even more significantly when one physically or mentally dislocated from the environment where the memory was created in. People always try to make memory more accessible by using or manipulating tangible objects, for example: photography, videotapes, and sound tracks. Not only to record life, but also to seek permanence since each human being only has limited time of consciousness. As memory, it’s permanent, as experience, it’s relatively temporary.