Need for cognitive closure predicts stress and anxiety of college students during COVID-19 pandemic.

The COVID-19 pandemic has taken a massive toll on mental well-being. The unprecedented level of uncertainty associated with the pandemic may be a contributing factor to stress and anxiety, especially among individuals with high intolerance to uncertainty (Rettie & Daniels, 2021). Individual differences in need for cognitive closure have also been linked to mental distress during unpredictable situations (Berenbaum et al., 2008). The present study tested the hypothesis that individuals with a high need for cognitive closure would experience relatively higher stress and anxiety during the COVID-19 pandemic. College students (N = 400) completed an abbreviated Need for Closure Scale (Roets & Van Hiel, 2011), the Generalized Anxiety Disorder Scale (Spitzer et al., 2006), and the short-version of the Perceived Stress Scale (Cohen & Williamson, 1988). Results supported the hypothesized relationship between high need for cognitive closure and higher levels of stress and anxiety. Findings have relevance to college students who are experiencing heightened psychological stress during the COVID-19 pandemic.

Chimeric protein A/G conjugate for detection of anti-Toxoplasma gondii immunoglobulin G in multiple animal species.

Serological testing for toxoplasmosis diagnosis remains the method of choice in human medicine due to the accessibility of the requisite sample, the difficulty in predicting the parasite's location in the host for direct detection, and the availability of established commercial methods. In veterinary medicine, although the first 2 conditions are unchanged, there is a need for commercially produced test methods that are validated for Toxoplasma gondii detection across the range of animal species that can serve as intermediate hosts. The development of such a serological method for animals would allow the diagnosis of toxoplasmosis in individual animals and a higher throughput method for population-level toxoplasmosis surveys. The incorporation of a non-species-specific chimeric protein A/G conjugate into an anti-Toxoplasma immunoglobulin G enzyme-linked immunosorbent assay is described. Serum from potential intermediate hosts was reevaluated using this method and compared with earlier testing using an established agglutination procedure. Very good agreement between the 2 tests was noted (κ = 0.81), establishing the method as a useful option for veterinary diagnostic testing.

Modification of a commercial Toxoplasma gondii immunoglobulin G enzyme-linked immunosorbent assay for use in multiple animal species.

A challenge faced by veterinary diagnosticians in serologic analysis for exposure to pathogens is the need for a protein conjugate capable of antibody attachment in many animal species. The advent of protein conjugates that are less specific in nature allows diagnosis across many species with little or no modification of technique. Toxoplasma gondii is an organism of veterinary interest that has been demonstrated to infect a plethora of warm-blooded animals. However, the serologic tests available for simultaneous diagnosis in this broad range are limited in number. The current study examined the use of an immunoglobulin G enzyme-linked immunosorbent assay (ELISA) modified by the use of non-species-specific protein conjugates in domestic animal species commonly submitted to diagnostic laboratories for evaluation of Toxoplasma exposure status. Comparison with results from an established indirect hemagglutination technique revealed very good agreement between the 2 test methods. This modification of the ELISA provides a useful method for veterinary diagnosticians to perform rapid and accurate evaluation of multiple animal species for Toxoplasma exposure using a single test.

ADHD and retrieval-induced forgetting: evidence for a deficit in the inhibitory control of memory.

Research on retrieval-induced forgetting has shown that the selective retrieval of some information can cause the forgetting of other information. Such forgetting is believed to result from inhibitory processes that function to resolve interference during retrieval. The current study examined whether individuals with ADHD demonstrate normal levels of retrieval-induced forgetting. A total of 40 adults with ADHD and 40 adults without ADHD participated in a standard retrieval-induced forgetting experiment. Critically, half of the items were tested using category cues and the other half of the items were tested using category-plus-one-letter-stem cues. Whereas both ADHD and non-ADHD participants demonstrated retrieval-induced forgetting on the final category-cued recall test, only non-ADHD participants demonstrated retrieval-induced forgetting on the final category-plus-stem-cued recall test. These results suggest that individuals with ADHD do have a deficit in the inhibitory control of memory, but that this deficit may only be apparent when output interference is adequately controlled on the final test.

Inhibitory control of proactive interference in adults with ADHD.

OBJECTIVE: Attention deficit hyperactivity disorder (ADHD) is associated with poor inhibition of prepotent responses and deficits in distractor inhibition, but relatively few studies have addressed inhibitory control of proactive interference (PI) in individuals with ADHD. Thus, the goal of the present study was to evaluate resistance to spatial and verbal PI in adults with ADHD. METHOD: Adults with ADHD (n = 32) and adults without ADHD (n = 32) performed a spatial inhibition of return (IOR) task and a semantic IOR task. RESULTS: Adults with and without ADHD showed effective spatial IOR. On the semantic IOR task, adults without ADHD showed semantic inhibition, whereas adults with ADHD showed semantic facilitation (positive priming) instead. CONCLUSION: Adults with ADHD may have domain-specific deficits in resistance to proactive interference. Research has theoretical and clinical implications for adults with ADHD.

Training attention-switching ability in adults with ADHD.

OBJECTIVE: Children with ADHD show attention-switching impairment. The present study assessed attention-switching ability in adults with ADHD, the extent to which this ability can be improved via targeted training, and the degree to which training extends to novel tasks of attention-switching. METHOD: Adults with ADHD (n = 16) and adults without ADHD (n = 18) were divided into training and non-training groups. Training groups performed six blocks of four different attention-switching tasks, while non-training groups completed non-switching, "filler" tasks. Lastly, the four groups were tested on two novel attention-switching tasks. RESULTS: Adults with ADHD showed impaired attention-switching, relative to non-ADHD adults, but training significantly improved attention-switching in both ADHD and non-ADHD training groups. Finally, training effects transferred to new tasks of attention-switching. CONCLUSION: Adults with ADHD show attention-switching impairments, but deficits may be ameliorated with short-term, targeted training. Research has implications for cognitive training in ADHD.

Attentional functioning and white matter integrity among survivors of malignant brain tumors of childhood.

Children surviving treatment for malignant brain tumors commonly have problems maintaining their premorbid levels of intellectual development and academic achievement. Our group has been especially interested in the effects of treatment on normal appearing white matter (NAWM) on MRI and the influence of NAWM volumes on neurocognitive functioning. The present study assessed NAWM and attentional abilities among 37 long-term survivors of malignant brain tumors, ranging in age from 1.7 to 14.8 (Mdn = 6.5) years at diagnosis, who had been treated with cranial radiation therapy with or without chemotherapy 2.6 to 15.3 (Mdn = 5.7) years earlier. On the Conners' Continuous Performance Test, the Overall Index and 7 of the other 10 indices were significantly deficient compared to age- and gender-corrected normative values. After statistically controlling for the effects of age at diagnosis and time elapsed from treatment, 5 of the 8 indices were significantly associated with cerebral white matter volumes and/or specific regional white matter volumes of the prefrontal/frontal lobe and cingulate gyrus. No gender effects were observed. The results of the present study further support the contention that NAWM is an important substrate for treatment-induced neurocognitive problems among survivors of malignant brain tumors of childhood.

Developmental model relating white matter volume to neurocognitive deficits in pediatric brain tumor survivors.

BACKGROUND: The primary objective of this study was to test the hypothesis that, among survivors of pediatric brain tumors, the association between reduced volumes of normal-appearing white matter (NAWM) and intellectual/academic achievement deficits can be explained by patient problems with memory and attention. METHODS: Quantitative tissue volumes from magnetic resonance imaging scans and neurocognitive assessments were obtained for 40 long-term survivors of pediatric brain tumors. They were treated with radiotherapy (RT) with or without chemotherapy 2.6-15.3 years earlier (median, 5.7 years) at an age of 1.7-14.8 years (median, 6.5 years). Neurocognitive assessments included standardized tests of intellect (intelligence quotient [IQ]), attention, memory, and academic achievement. RESULTS: Analyses revealed significant impairments in patients' neurocognitive test performance on all measures. After statistically controlling for age at RT and time from RT, significant associations were found between NAWM volumes and both attentional abilities and IQ, and between attentional abilities and IQ. Subsequent analyses supported the hypothesis that attentional abilities, but not memory, could explain a significant amount of the relationship between NAWM and IQ. The final developmental model predicting academic achievement based on NAWM, attentional abilities, and IQ explained approximately 60% of the variance in reading and spelling and almost 80% of the variance in math. CONCLUSIONS: The authors demonstrated that the primary consequence of reduced NAWM among pediatric patients treated for brain tumors was decreased attentional abilities, leading to declining IQ and academic achievement.