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This study demonstrates that overtraining in temporal discrimination modifies temporal stimulus control in a bisection task and produces habitual responding, as evidenced through insensitivity to food devaluation. Rats were trained or overtrained in a 2-versus 8-sec temporal discrimination task, with each duration associated with a lever (left or right) and food (grain or sucrose). Overtraining produced a leftward shift in the bisection point. Devaluation treatment induced a differential loss of responding depending on stimulus duration (short versus long) and the level of training (training versus overtraining). The relationships between timing behavior and habitual behavior are discussed.

Introduction: Hospital-acquired infections (HAIs) after stroke are associated with additional morbidity and mortality, but whether HAIs increase long-term cognitive decline in stroke patients is unknown. We hypothesized that older adults with incident stroke with HAI experience faster cognitive decline than those having stroke without HAI and those without stroke. Methods: We performed a longitudinal analysis in the population-based prospective Cardiovascular Health Study. Medicare-eligible participants aged ≥65 years with and without incident stroke had cognition assessed annually. HAIs were assessed by hospital discharge codes. Global cognitive function was assessed annually by the Modified Mini-Mental State Examination (3MSE) and executive function by the Digit Symbol Substitution Test (DSST). We used linear mixed models to estimate the mean decline and 95% confidence intervals (95% CI) for 3MSE and DSST scores by incident stroke and HAI status, adjusted for demographics and vascular risk factors. Results: Among 5,443 participants ≥65 years without previous history of stroke, 393 participants had stroke with HAI (SI), 766 had a stroke only (SO), and 4,284 had no stroke (NS) throughout a maximum 9-year follow-up. For 3MSE, compared with NS participants, SO participants had a similar adjusted mean decline (additional 0.08 points/year, 95% CI: −0.15, 0.31), while SI participants had a more rapid decline (additional 0.28 points/year, 95% CI: 0.16, 0.40). Adjusted mean decline was 0.20 points/year faster (95% CI: −0.05, 0.45) among SI than SO participants. For DSST, compared with NS participants, SO participants had a faster adjusted mean decline (additional 0.17 points/year [95% CI: 0.003, 0.33]), as did SI participants (additional 0.27 points/year [95% CI: 0.19, 0.35]). Conclusion: Stroke, when accompanied by HAI, leads to a faster long-term decline in cognitive ability than in those without stroke. The clinical and public health implications of the effect of infection on post-stroke cognitive decline warrant further attention. [ABSTRACT FROM AUTHOR]

The accuracy of time judgments depends upon many factors, including the sensory properties of the to-be-timed stimulus. In auditory Pavlovian fear conditioning, an initially neutral tone (conditioned stimulus, CS) predicts the arrival of an aversive event (unconditioned stimulus, US) at a fixed time interval. The temporal relation between the CS and US events is encoded, leading to the development of a temporal pattern of responding. Little attention has been paid to the potential impact of the characteristics of the CS tone on the development of this temporal pattern. Here we compared the acquisition of the temporal pattern of conditioned responses of rats to different CS tone frequencies. Rats were first conditioned to lever press for food. Then, while lever pressing for food, they were presented with 60-s tones  of two very different frequencies 1kHz or 11kHz, each paired with a foot-shock given 30s after tone onset. This fear conditioning led to the appearance of conditioned suppression of the lever pressing. On probe trials the tone duration was 60 s, and the reinforcer was omitted. With training, a pattern of suppression evolved during the probe trials, showing a maximum of suppression near the programmed time of the shock US, however the 11kHz CS tone yielded better temporal control than did the 1kHz tone. A second experiment investigated rats’ abilities to discriminate between two times of shock arrival (10s or 30s) predicted by the different tone frequencies (1kHz or 11kHz), In this experiment, rats showed poorer discriminative timing performance when the lower frequency (1kHz) was associated with the longer duration (30s). Our results suggest a strong impact of the CS sensory properties on the expression of temporal learning within the context of auditory fear conditioning in rats.

The effects of two training procedures -- (a) modeling and praise and (b) self-instruction, modeling, and praise -- on complex gross-motor chain acquisition for preschool dance class students were evaluated. Six girls participated in the study. A multiple baseline design across six gross-motor chains with a secondary group comparison for treatment order effects was used. Both procedures were effective in teaching the gross-motor chains. Nevertheless, for 4 of the 6 participants, the self-instruction procedure produced a faster acquisition rate in at least two of the three comparable pairs of gross-motor chains. Furthermore, very early in gross-motor chain acquisition, for five of the six gross-motor chains, the self-instruction condition was associated with faster response acquisition.

Opioid use disorder (OUD)-associated overdose deaths have reached epidemic proportions worldwide over the past two decades, with death rates for men reported at twice the rate for women. Using a controlled, cross-sectional, age-matched (18–56 y) design to better understand the cognitive neuroscience of OUD, we evaluated the electroencephalographic (EEG) responses of male and female participants with OUD vs. age- and gender-matched non-OUD controls during a simple visual object recognition Go/No-Go task. Overall, women had significantly slower reaction times (RTs) than men. In addition, EEG N200 and P300 event-related potential (ERP) amplitudes for non-OUD controls were significantly larger for men, while their latencies were significantly shorter than for women. However, while N200 and P300 amplitudes were not significantly affected by OUD for either men or women in this task, latencies were also affected differentially in men vs. women with OUD. Accordingly, for both N200 and P300, male OUD participants exhibited longer latencies while female OUD participants exhibited shorter ones than in non-OUD controls. Additionally, robust oscillations were found in all participants during a feedback message associated with performance in the task. Although alpha and beta power during the feedback message were significantly greater for men than women overall, both alpha and beta oscillations exhibited significantly lower power in all participants with OUD. Taken together, these findings suggest important gender by OUD differences in cognitive processing and reflection of performance in this simple visual task. [ABSTRACT FROM AUTHOR]

The purpose of this study was to compare transformational and instructional leadership theories, examine the unique impact that school leaders have on student achievement, and determine which specific leadership practices are associated with increased student achievement. The sample for this study consisted of 590 teachers in 37 elementary schools in the Intermountain West of the United States. Teachers rated their principals' leadership style according to the Multifactor Leadership Questionnaire (Transformational Leadership) and the Principal Instructional Management Rating Scale (Instructional leadership). Student achievement was measured by a criterion referenced test. Hypotheses were tested using regression analysis. Results indicated that instructional leadership explained more of the variance in student achievement than did transformational leadership. Principals' leadership style tended to have a meaningful impact on student achievement beyond the impact of school context and principal demographics. Specific leadership functions associated with student achievement were also identified and reported. Conclusion, implications and limitations are also discussed.

Associated with gastritis, peptic-ulcer disease, and gastric carcinoma, Helicobacter pylori (H. pylori) also has been associated with decreased cognitive function and dementia. In this study, we used data from the UK Biobank to further examine associations between H. pylori seropositivity and serointensity and performance on several cognitive tasks in adults 40 to 70 years of age (M = 55.3, SD = 8.1). In these analyses, H. pylori seropositivity (i.e., either positive or negative for H. pylori) and serointensity (concentration of antibodies against H. pylori antigens) in adjusted models were associated with worse function on tasks of Numeric memory, Reasoning, and errors on the Pairs matching test but better function on the Tower rearrangement task. Together, these findings suggest that H. pylori seropositivity and serointensity might be associated with worse cognitive function in this age group. [ABSTRACT FROM AUTHOR]

Three children diagnosed with pervasive developmental disabilities emitted a high rate of mands and a low-to-zero rate of appropriate play responses when the two responses were reinforced on concurrent Fixed Ratio 1 (FR1) schedules. When mands were reinforced on an FR10 schedule and play responses were concurrently reinforced on an FR1 schedule, play responses increased. Two participants' mands decreased from baseline levels but were maintained, and the third participant's mands increased. Implications of the use of choice procedures for clinical settings are discussed. (Contains 2 figures.)

Recent advances in electronic data collection have opened broad new possibilities for educational assessment. Potentially significant savings in time, money, and effort make Web-based and e-mail-based surveys more and more attractive as alternatives to mail surveys and face-to-face interviews. Yet, as with any major change, questions and obstacles arise. Software packages require financial commitment, as well as hardware and programming support. There are also questions regarding the validity of electronically collected data. This study has two principal purposes. The first is to examine the practical, logistical advantages and disadvantages of electronic versus paper administration techniques for a large-scale survey project. The second is to evaluate the relative agreement of data received using electronic versus paper collection processes. The results of this research suggest that after the initial investment and learning curve, significant savings in time and effort, substantially quicker turn-around time and potentially richer data resulted from the electronic process. The main downsides include the initial cost of the software and greater technical support needed to configure and operate the programs successfully.

Pigeons were exposed to a random relation between a conditioned stimulus (CS) and an unconditioned stimulus (US) under the signaled random procedure. All US presentations that were unpaired with the CS were preceded by a second cue, a cover stimulus. Consistent with prior studies, the signaled random procedure supported responding during the CS; however, magnitude of this cover-stimulus effect varied with the duration of the CS relative to the cover-stimulus duration. Higher levels of responding were maintained when the CS and cover stimulus were equal versus unequal in duration. Experiment 1 provides a systematic replication of a study by Williams (1994), who used rat subjects. Higher levels of CS-directed responding were maintained when the cover stimulus was equal in duration to the CS versus when it was shorter. Experiment 2 provides the first demonstration of the effects of cover-stimulus durations that are both longer and shorter than the CS duration, compared to a procedure in which the durations are equivalent. In support of a stimulus-duration-equality effect, level of responding was higher for all equal stimulus-duration groups in comparison to unequal stimulus-duration comparison groups. These effects were accommodated by a common-elements generalization approach to the Rescorla-Wagner model.

Abstract Social anxiety disorder is associated with impairment in social and occupational functioning, significant personal distress and a possible economic burden, resulting in a reduction in quality of life. To [...]

The effects of two training procedures--(a) modeling and praise and (b) self-instruction, modeling, and praise--on complex gross-motor chain acquisition for preschool dance class students were evaluated. Six girls participated in the study. A multiple baseline design across six gross-motor chains with a secondary group comparison for treatment order effects was used. Both procedures were effective in teaching the gross-motor chains. Nevertheless, for 4 of the 6 participants, the self-instruction procedure produced a faster acquisition rate in at least two of the three comparable pairs of gross-motor chains. Furthermore, very early in gross-motor chain acquisition, for five of the six gross-motor chains, the self-instruction condition was associated with faster response acquisition. DESCRIPTORS: acquisition, dance, gross-motor chains, modeling, self-instruction, training procedures

Previous studies suggest that the effect of color on object identification differs depending upon the type of object identification response required of participants. In the present study, presence versus absence of color (chromaticity) was manipulated under two object identification tasks--speeded naming (priming) and recognition. In a replication and extension of Biederman and Cooper (1992), college students were exposed to a list of 28, 2-dimensional representations of common objects, presented two times in succession (Blocks 1 and 2). Participants orally named each stimulus in Block 1 as it appeared. Under a speeded naming task (Experiments 1 and 2), participants named each stimulus again in Block 2, whereas they produced a recognition response in Experiment 3. For the recognition task, participants were instructed to respond 'same' if an object had the same shape as one presented previously, and 'different' if it did not. Shape and/or size (Experiment 1) or shape and/or chromaticity (Experiments 2 and 3) of the objects could change between their first and second exposures. Changes in shape increased the latencies of correct speeded naming responses in both Experiments 1 and 2, whereas changes in size and chromaticity did not. In contrast, changes in chromaticity resulted in a sharp increase in recognition latencies for 'same' responses in Experiment 3. The results indicate that object chromaticity was incidentally coded during the first exposure even though this stimulus dimension did not affect speeded naming. The results are consistent with a history of differential reinforcement of stimulus response relationships for different object-identification responses., One objective of the present study was to systematically replicate Biederman and Cooper's research. A second objective was to extend that investigation to the stimulus attribute of color by evaluating [...]

Results of an experiment with pigeons tend to support memory retrieval theories in which unreinforced trials serve as a retrieval cue for not responding. Eliminating autoshaped responding by random or negatively-contingent response-reductive methods may not eliminate a previously acquired association. In two experiments, the autoshaped responding of pigeons was gotten rid of by a backward or negative contingency.

Temporal control of behavior was investigated within the framework of an internal clock model. Pigeons were exposed to signaled fixed-interval 30-s trials mixed with extended unreinforced (baseline) trials. On unreinforced break trials, the signal was interrupted for a period of time after trial onset. In Experiment 1, comparisons between the peak time obtained on baseline and on break trials produced peak time shifts that were longer than those expected if the clock had stopped during the break but shorter than if the clock had reset. In Experiment 2, systematic manipulations of duration and location of breaks produced peak time shifts that were nonlinear functions of break duration and that varied linearly with break location. The obtained peak times were more consistent with a continuous memory decay model than with the stop-retain or the reset hypotheses.

The intracellular protozoal parasite Toxoplasma gondii has been associated with worsened cognitive function in animal models and in humans. Despite these associations, the mechanisms by which Toxoplasma gondii might affect cognitive function remain unknown, although Toxoplasma gondii does produce physiologically active intraneuronal cysts and appears to affect dopamine synthesis. Using data from the UK Biobank, we sought to determine whether Toxoplasma gondii is associated with decreased prefrontal, hippocampal, and thalamic gray-matter volumes and with decreased total gray-matter and total white-matter volumes in an adult community-based sample. The results from adjusted multivariable regression modelling showed no associations between Toxoplasma gondii and prefrontal, hippocampal, and thalamic brain gray-matter volumes. In contrast, natural-log transformed antibody levels against the Toxoplasma gondii p22 (b = -3960, 95-percent confidence interval, -6536 to -1383, p <.01) and sag1 (b = -4863, 95-percent confidence interval, –8301 to -1425, p <.01) antigens were associated with smaller total gray-matter volume, as was the mean of natural-log transformed p22 and sag1 titers (b = -6141, 95-percent confidence interval, -9886 to -2397, p <.01). There were no associations between any of the measures of Toxoplasma gondii and total white-matter volume. These findings suggest that Toxoplasma gondii might be associated with decreased total gray-matter in middle-aged and older middle-aged adults in a community-based sample from the United Kingdom. [ABSTRACT FROM AUTHOR]

Introduction: Recent clinical trials are considering inclusion of more than just apolipoprotein E (APOE) ε4 genotype as a way of reducing variability in analysis of outcomes. Methods: Case‐control data were used to compare the capacity of age, sex, and 58 Alzheimer's disease (AD)–associated single nucleotide polymorphisms (SNPs) to predict AD status using several statistical models. Model performance was assessed with Brier scores and tenfold cross‐validation. Genotype and sex × age estimates from the best performing model were combined with age and intercept estimates from the general population to develop a personalized genetic risk score, termed age, and sex‐adjusted GenoRisk. Results: The elastic net model that included age, age x sex interaction, allelic APOE terms, and 29 additional SNPs performed the best. This model explained an additional 19% of the heritable risk compared to APOE genotype alone and achieved an area under the curve of 0.747. Discussion: GenoRisk could improve the risk assessment of individuals identified for prevention studies. [ABSTRACT FROM AUTHOR]

Infecting approximately one-third of the world's human population, Toxoplasma gondii has been associated with cognitive function. Here, we sought to further characterize the association between Toxoplasma gondii and cognitive function in a community sample of adults aged approximately 40 to70 years. Using adjusted linear regression models, we found associations of Toxoplasma gondii seropositivity with worse reasoning (b = -.192, p <.05) and matrix pattern completion (b = -.681, p <.01), of higher anti-Toxoplasma gondii p22 antibody levels with worse reasoning (b = -.078, p <.01) and slower Trails (numeric) performance (b = 5.962, p <.05), of higher anti-Toxoplasma gondii sag1 levels with worse reasoning (b = -.081, p <.05) and worse matrix pattern completion (b = -.217, p <.05), and of higher mean of the anti-Toxoplasma gondii p22 and sag1 levels with worse reasoning (b = -.112, p <.05), slower Trails (numeric) performance (b = 9.195, p <.05), and worse matrix pattern completion (b = -.245, p <.05). Neither age nor educational attainment moderated associations between the measures of Toxoplasma gondii seropositivity or serointensity. Sex, however, moderated the association between the sag1 titer and digit-symbol substitution and the association between the mean of the p22 and sag1 levels and digit-symbol substitution, and income moderated the association between Toxoplasma gondii seropositivity and numeric memory and the association between the p22 level and symbol-digit substitution. Based on the available neuropsychological tasks in this study, Toxoplasma gondii seropositivity and serointensity were associated with some aspects of poorer executive function in adults. Author summary: Toxoplasma gondii is a parasite that reproduces in cats but that can infect other animals and humans. Toxoplasma gondii has an affinity for the brain and infection results in a long-term immune response that may have negative effects. Animal models have shown that Toxoplasma gondii can affect behavior and cognition (thinking). In humans, the association is less clear, but there are associations between infection and variety of psychiatric and neurological conditions such as schizophrenia and epilepsy. Toxoplasma gondii may even increase the risk of dementia. If true, it is possible that the presence of this infection may affect thinking long before the onset of dementia. We sought to determine if the presence of antibodies in the blood to Toxoplasma gondii, which is the immune system's response to past infections, might be associated with performance on measures of cognition. We analyzed a large dataset, the UK Biobank, which includes measures of cognition and blood test results for antibodies to Toxoplasma gondii. We found that both the presence of antibodies as well as the amount of these antibodies were related to some aspects of cognition, particularly problem solving and reasoning in otherwise healthy adults ages 40 to 69 years. [ABSTRACT FROM AUTHOR]

Background: Air pollution has been associated with cognitive function and brain volume. While most previous research has examined the association between air pollution and brain volume in cortical structures or total brain volume, less research has investigated associations between exposure to air pollution and subcortical structures, including the thalamus. Further, the few available previous studies investigating associations between air pollution and thalamic volume have shown mixed results. Methods: In this study, we evaluated the association between PM2.5, PM2.5–10, PM10, nitrogen dioxide, and nitrogen oxides and volume of the thalamus in adults using the UK Biobank resource, a large community-based sample, while adjusting for multiple covariates that could confound an association between air pollution and thalamic volume. Results: In adjusted models, the left but not right thalamus volume was significantly inversely associated with PM2.5–10, although there were no significant associations between PM2.5, PM10, nitrogen dioxide, and nitrogen oxides with either left or right thalamic volumes. In addition, interactions between age and PM2.5–10 and PM10 were inversely associated with thalamic volume, such that thalamic volume in older people appeared more vulnerable to the adverse effects of PM2.5–10 and PM10, and interactions between educational attainment and PM2.5, nitrogen dioxide, and nitrogen oxides and between self-rated health and PM2.5–10 were positively associated with thalamic volume, such that higher educational attainment and better self-rated health appeared protective against the adverse effects of air pollution on the thalamus. Conclusion: These findings suggest a possible association between thalamic volume and air pollution particularly in older people and in people with comparatively low educational attainment at levels of air pollution found in the United Kingdom. [ABSTRACT FROM AUTHOR]

Background: Infectious diseases might affect cognitive aging and dementia risk, possibly via neuroinflammation. Similarly, risk factors for cardiovascular and cerebrovascular diseases are associated with cognitive function and dementia. We hypothesized that cardiovascular risk factors moderate the association of exposure to infectious diseases with cognitive function. Methods: We studied 5662 participants aged 20 to 59 years from the third National Health and Nutrition Examination Survey (1988–1994) in the United States. We used linear regression to investigate whether the Framingham general cardiovascular risk index moderated the association of infection burden based on exposure to eight different infectious diseases with cognitive functioning as measured by the Symbol Digit Substitution, Serial Digit Learning, and Reaction Time tests. Results: The multiplicative interaction between the infection-burden index and the cardiovascular-risk index was associated with performance on the Symbol Digit Substitution (B = .019 [95% CI: .008, .031], p < .001) but not on the Serial Digit Learning (B = .034 [95% CI: -.025, .094]) or for Reaction Time (B = -.030 [95% CI: -.848, .787]). Participants with a lower cardiovascular risk appeared to be more resilient against the potential adverse effects of higher infection burden on the Symbol Digit Substitution task. Conclusions: Participants at zero risk for a cardiovascular event in the next 10 years had no differences in processing speed with increasing exposure to infectious disease, whereas participants with higher risk for a cardiovascular event had worse processing speed with increased exposure to infectious disease. [ABSTRACT FROM AUTHOR]