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1.  Event Segmentation Ability Uniquely Predicts Event Memory 
Cognition  2013;129(2):10.1016/j.cognition.2013.07.002.
Memory for everyday events plays a central role in tasks of daily living, autobiographical memory, and planning. Event memory depends in part on segmenting ongoing activity into meaningful units. This study examined the relationship between event segmentation and memory in a lifespan sample to answer the following question: Is the ability to segment activity into meaningful events a unique predictor of subsequent memory, or is the relationship between event perception and memory accounted for by general cognitive abilities? Two hundred and eight adults ranging from 20 to 79 years old segmented movies of everyday events and attempted to remember the events afterwards. They also completed psychometric ability tests and tests measuring script knowledge for everyday events. Event segmentation and script knowledge both explained unique variance in event memory above and beyond the psychometric measures, and did so as strongly in older as in younger adults. These results suggest that event segmentation is a basic cognitive mechanism, important for memory across the lifespan.
PMCID: PMC3821069  PMID: 23942350
Event cognition; Episodic memory; Cognitive aging
2.  Adherence to antiretroviral therapy during pregnancy and the first year postpartum among HIV-positive women in Ukraine 
BMC Public Health  2014;14(1):993.
Poor adherence to antiretroviral therapy (ART) is associated with HIV disease progression and, during pregnancy, increased mother-to-child transmission risk. In Ukraine, access to combination ART is expanding but data on adherence are scarce.
Cross-sectional surveys of HIV-positive women were conducted i) at delivery (on antenatal ART adherence) and ii) during the first year postpartum (on ART adherence in the preceding four weeks). Factors associated with a score ≤11 on the self-report Case Adherence Support Evaluation (CASE) index or ≥1 self-reported missed dose were assessed using Fisher’s exact test.
Of 185 antenatal participants and 102 postnatal participants, median ages were 27.5 and 29.5 years respectively: 28% (50/180) and 27% (26/98) reported an unplanned pregnancy, and 13% (24/179) and 17% (17/98) an illicit drug-use history (excluding marijuana). One quarter (49/180 antenatally, 27/101 postnatally) screened positive for depression. The proportion reporting ‘low’ ART-related self-efficacy (i.e. unable to do ≥1/5 ART-taking activities) was 20% (28/141) antenatally and 17% (11/66) postnatally. Antenatally, 14% (95% CI 10-21%) had a CASE score ≤11 and 35% (95% CI 28-42%) reported missing ≥1 dose. Factors associated with a CASE score ≤11 were unplanned pregnancy (25% (12/48) vs. 11% (13/120) where planned, p = 0.03) and living with extended family (23% (13/57) vs. 10% (12/125) living with partner/alone, p = 0.04). Self-report of ≥1 missed dose antenatally was additionally associated with younger age (p = 0.03) and lower self-efficacy (50% (14/28) reported ≥1 missed dose vs. 28% (30/108) of those with high self-efficacy, p = 0.04). Of 102 postnatal participants, 8% (95% CI 4-15%) had a CASE score ≤11 and 31% (95% CI 22-41%) reported ≥1 missed dose. Of 11 women with low self-efficacy, 3 (27%) had a CASE score ≤11 compared with 3/55 (5%) of those with high self-efficacy (p = 0.05). Current smokers more commonly reported ≥1 missed dose postnatally (50% (13/26) vs. 25% (18/72) of non-smokers, p = 0.03).
Our results highlight unmet needs for counselling and support. We identify some groups at risk of poor ART adherence, including women with markers of social vulnerability and those with low ART-related self-efficacy, who may benefit from targeted interventions.
PMCID: PMC4180980  PMID: 25248469
HIV; Antiretroviral therapy; Adherence; Self-efficacy; Ukraine; Eastern Europe; Women; Pregnancy; Prevention of mother-to-child transmission
3.  Action perception predicts action performance 
Neuropsychologia  2013;51(11):2294-2304.
Everyday action impairments often are observed in demented older adults, and they are common potential barriers to functional independence. We evaluated whether the ability to segment and efficiently encode activities is related to the ability to execute activities. Further, we evaluated whether brain regions important for segmentation also were important for action performance. Cognitively healthy older adults and those with very mild or mild dementia of the Alzheimer's type watched and segmented movies of everyday activities and then completed the Naturalistic Action Test. Structural MRI was used to measure volume in the dorsolateral prefrontal cortex (DLPFC), medial temporal lobes (MTL), posterior cortex, and anterior cingulate cortex (ACC). Dementia status and the ability to segment everyday activities strongly predicted naturalistic action performance, and MTL volume largely accounted for this relationship. In addition, the current results supported the Omission-Commission Model: Different cognitive and neurological mechanisms predicted different types of action error. Segmentation, dementia severity, and MTL volume predicted everyday omission errors, DLPFC volume predicted commission errors, and ACC volume predicted action additions. These findings suggest that event segmentation may be critical for effective action production, and that the segmentation and production of activities may recruit the same event representation system.
PMCID: PMC3936325  PMID: 23851113
Perception; Segmentation; Action performance; MTL volume; Dementia
4.  Medial Temporal Lobe Volume Predicts Elders' Everyday Memory 
Psychological science  2013;24(7):1113-1122.
Deficits in memory for everyday activities are common complaints among healthy and demented older adults. The medial temporal lobes and dorsolateral prefrontal cortex are both affected by aging and early-stage Alzheimer's disease, and are known to influence performance on laboratory memory tasks. We investigated whether the volume of these structures predicts everyday memory. Cognitively healthy older adults and older adults with mild Alzheimer's-type dementia watched movies of everyday activities and completed memory tests on the activities. Structural MRI was used to measure brain volume. Medial temporal but not prefrontal volume strongly predicted subsequent memory. Everyday memory depends on segmenting activity into discrete events during perception, and medial temporal volume partially accounted for the relationship between performance on the memory tests and performance on an event-segmentation task. The everyday-memory measures used in this study involve retrieval of episodic and semantic information as well as working memory updating. Thus, the current findings suggest that during perception, the medial temporal lobes support the construction of event representations that determine subsequent memory.
PMCID: PMC3936320  PMID: 23630222
perception; memory; cognitive neuroscience; aging
5.  Insufficient antiretroviral therapy in pregnancy: missed opportunities for prevention of mother-to-child transmission of HIV in Europe 
Antiviral therapy  2011;16(6):895-903.
Although mother-to-child transmission (MTCT) rates are at an all-time low in Western Europe, potentially preventable transmissions continue to occur. Duration of antenatal combination antiretroviral therapy (ART) is strongly associated with MTCT risk.
Data on pregnant HIV-infected women enrolled in the Western and Central European sites of the European Collaborative Study between January 2000 and July 2009 were analysed. The proportion of women receiving no antenatal ART or 1-13 days of treatment was investigated, and associated factors explored using logistic regression models.
Of 2148 women, 142 (7%) received no antenatal ART, decreasing from 8% in 2000-03 to 5% in 2004-09 (χ2 =8.73, p<0.01). A further 41 (2%) received 1-13 days of ART. A third (64/171) of women with “insufficient” (no or 1-13 days) antenatal ART had a late HIV diagnosis (in the third trimester or intrapartum), but half (85/171) were diagnosed pre-conception. Preterm delivery <34 weeks was associated with receipt of no and 1-13 days antenatal ART (AOR 2.9 p<0.01 and AOR 4.5 p<0.01 respectively). Injecting drug use history was associated with an increased risk of no ART (AOR 2.9 p<0.01) and severe symptomatic HIV disease with a decreased risk (AOR 0.2, p<0.01). MTCT rates were 1.1% (15/1318) among women with ≥14 days antenatal ART and 7.4% (10/136) among those with insufficient ART.
Over the last 10 years, around 1 in 11 women in this study received insufficient antenatal ART, accounting for 40% of mother-to-child transmissions. Half of these women were diagnosed pre-conception, suggesting disengagement from care.
PMCID: PMC3428867  PMID: 21900722
6.  Factors associated with abandonment of infants born to HIV positive women: results from a Ukrainian birth cohort 
AIDS care  2010;22(12):1439-1448.
Social marginalisation and other challenges facing HIV-positive pregnant women in Ukraine may put them at increased risk of relinquishing their infants to the state. We described rates of infant abandonment (exclusive non-parental care to most recent follow up, censored at two years of age) and investigated associated factors using logistic regression models, in 4759 mother-infant pairs enrolled across six Ukrainian sites in the European Collaborative Study from 2000 to May 2009. Median maternal age was 26.0 years, 81.8% were married or cohabiting and 60.6% were nulliparous at enrolment. An injecting drug use (IDU) history was reported by 18.4%, 80.2% took antiretroviral therapy (ART) antenatally and most deliveries were vaginal. A small but significant proportion of infants had been cared for exclusively in institutions by their second birthday (2.1% overall), decreasing from 3.8% (15/393) in 2000-02 to 1.6% (49/3136) in 2006-09 (p<0.01), concurrent with prevention of mother-to-child transmission (PMTCT) scale-up. A further 1% of infants spent some time in non-parental care. Antenatal ART was associated with an 88% reduced abandonment risk (AOR 0.12), versus receipt of single dose nevirapine only, and this was reflected in HIV infection prevalence in the two groups (17.1% of abandoned infants versus 6.6% in parental care). Mothers without a cohabiting partner or husband were more likely to abandon (AOR 4.08), as were active IDUs (AOR 3.27) and those with ≥1 previous children (AOR 1.89 for second-born, AOR 2.56 for subsequent births). Women delivering by elective caesarean section were less likely to abandon (AOR 0.37 versus vaginal), as were those leaving full time education later (AOR 0.61 for 17-18 years versus ≤16 years, AOR 0.23 for ≥19 years versus ≤16 years). Interventions to extend family planning and IDU harm reduction services along with non-stigmatising antenatal care to marginalised women are needed, and may reduce abandonment.
PMCID: PMC3428901  PMID: 20824547
HIV; infant abandonment; antenatal antiretroviral therapy; injecting drug use; Ukraine
7.  Cervical Screening within HIV Care: Findings from an HIV-Positive Cohort in Ukraine 
PLoS ONE  2012;7(4):e34706.
HIV-positive women have an increased risk of invasive cervical cancer but cytologic screening is effective in reducing incidence. Little is known about cervical screening coverage or the prevalence of abnormal cytology among HIV-positive women in Ukraine, which has the most severe HIV epidemic in Europe.
Poisson regression models were fitted to data from 1120 women enrolled at three sites of the Ukraine Cohort Study of HIV-infected Childbearing Women to investigate factors associated with receiving cervical screening as part of HIV care. All women had been diagnosed as HIV-positive before or during their most recent pregnancy. Prevalence of cervical abnormalities (high/low grade squamous intraepithelial lesions) among women who had been screened was estimated, and associated factors explored.
Overall, 30% (337/1120) of women had received a cervical screening test as part of HIV care at study enrolment (median 10 months postpartum), a third (115/334) of whom had been tested >12 months previously. In adjusted analyses, women diagnosed as HIV-positive during (vs before) their most recent pregnancy were significantly less likely to have a screening test reported, on adjusting for other potential risk factors (adjusted prevalence ratio (APR) 0.62, 95% CI 0.51–0.75 p<0.01 for 1st/2nd trimester diagnosis and APR 0.42, 95% CI 0.28–0.63 p<0.01 for 3rd trimester/intrapartum diagnosis). Among those with a cervical screening result reported at any time (including follow-up), 21% (68/325) had a finding of cervical abnormality. In adjusted analyses, Herpes simplex virus 2 seropositivity and a recent diagnosis of bacterial vaginosis were associated with an increased risk of abnormal cervical cytology (APR 1.83 95% CI 1.07–3.11 and APR 3.49 95% CI 2.11–5.76 respectively).
In this high risk population, cervical screening coverage as part of HIV care was low and could be improved by an organised cervical screening programme for HIV-positive women. Bacterial vaginosis testing and treatment may reduce vulnerability to cervical abnormalities.
PMCID: PMC3335834  PMID: 22545087
8.  Metacognitive Training at Home: Does It Improve Older Adults' Learning? 
Gerontology  2009;56(4):414-420.
Previous research has described the success of an intervention aimed at improving older adults' ability to regulate their learning. This metacognitive approach involves teaching older adults to allocate their study time more efficiently by testing themselves and restudying items that are less well learned.
Although this type of memory intervention has shown promise, training older adults to test themselves in the laboratory can be very time-intensive. Thus, the purpose of the present study is to transport the self-testing training method from the laboratory to home use.
A standard intervention design was used that included a pretraining session, multiple training sessions, and a posttraining session. Participants were randomly assigned to either the training group (n = 29) or the waiting list control group (n = 27). Moreover, we screened participants for whether they used the self-testing strategy during their pretraining test session.
Compared to the performance of the control group, the training group displayed significant gains, which demonstrates that older adults can benefit from training themselves to use these skills at home. Moreover, the results of the present study indicate that this metacognitive approach can effectively improve older adults' learning, even in those who spontaneously self-test prior to training.
Training metacognitive skills, such as self-testing and efficient study allocation, can improve the ability to learn new information in healthy older adults. More importantly, older adult clients can be supplied with an at-home training manual, which will ease the burden on practitioners.
PMCID: PMC2917739  PMID: 20016124
Memory intervention; At-home training; Self-testing training method; Metacognitive skills; Memory competence
9.  Does Differential Strategy Use Account for Age-Related Deficits in Working-Memory Performance? 
Psychology and aging  2009;24(1):82-92.
The strategy-deficit hypothesis states that age differences in the use of effective strategies contribute to the age-related deficits in working memory (WM) span performance. To evaluate this hypothesis, strategy use was measured using set-by-set strategy reports during the reading span (RSPAN) task (Experiments 1 and 2) and the operation span (OSPAN) task (Experiment 2). Individual differences in the reported use of effective strategies accounted for substantial variance in span performance. In contrast to the strategy-deficit hypothesis, however, young and older adults reported using the same proportion of normatively effective strategies on both span tasks. Measures of processing speed accounted for a substantial proportion of the age-related variance in span performance. Thus, although using normatively effective strategies accounts for individual differences in span performance, age differences in effective strategy use cannot explain the age-related variance in that performance.
PMCID: PMC2658624  PMID: 19290740

Results 1-9 (9)