Steven P. Verney

Pupillary responses and processing resources on the visual backward masking task

Task-evoked pupillary responses were recorded during a visual backward masking task as an index of resource allocation. Increased pupillary dilation indicates increased allocation of processing resources to the task. Consistent with numerous studies, detection accuracy increased with longer interstimulus intervals and approximated no-mask accuracy in the 300-ms condition. Pupillary dilation responses were significantly greater during task performance (cognitive load) than during a passive stimulus viewing condition (no-load) and were significantly greater in the 300-ms condition than the no-mask condition. Consistent with models of early visual information processing, the results suggest that the mask demanded extra processing resources when it followed the target by more than 100 ms. Pupillography methods may be useful in evaluating the contribution and timing of resource-demanding processes during early visual information processing.

Control of rodent and human spatial navigation by room and apparatus cues

A growing body of literature indicates that rats prefer to navigate in the direction of a goal in the environment (directional responding) rather than to the precise location of the goal (place navigation). This paper provides a brief review of this literature with an emphasis on recent findings in the Morris water task. Four experiments designed to extend this work to humans in a computerized, virtual Morris water task are also described. Special emphasis is devoted to how directional responding and place navigation are influenced by room and apparatus cues, and how these cues control distinct components of navigation to a goal. Experiments 1 and 2 demonstrate that humans, like rats, perform directional responses when cues from the apparatus are present, while Experiment 3 demonstrates that place navigation predominates when apparatus cues are eliminated. In Experiment 4, an eyetracking system measured gaze location in the virtual environment dynamically as participants navigated from a start point to the goal. Participants primarily looked at room cues during the early segment of each trial, but primarily focused on the apparatus as the trial progressed, suggesting distinct, sequential stimulus functions. Implications for computational modeling of navigation in the Morris water task and related tasks are discussed.

Reducing health disparities through a culturally centered mentorship program for minority faculty: the Southwest Addictions Research Group (SARG) experience.

Purpose Ethnic minority faculty members are vastly underrepresented in academia. Yet, the presence of these individuals in academic institutions is crucial, particularly because their professional endeavors often target issues of health disparities. One promising way to attract and retain ethnic minority faculty is to provide them with formal mentorship. This report describes a culturally centered mentorship program, the Southwest Addictions Research Group (SARG, 2003-2007), at the University of New Mexico (UNM) that trained a cadre of minority researchers dedicated to reducing health disparities associated with substance abuse. Method The SARG was based at UNM’s School of Medicine’s Institute for Public Health, in partnership with the UNM’s Center on Alcoholism, Substance Abuse, and Addictions. The program consisted of regular research meetings, collaboration with the Community Advisory Board, monthly symposia with renowned professionals, pilot projects, and conference support. The authors collected data on mentee research productivity as outcomes and conducted separate mentee and mentor focus-group interviews to assess the strengths and weaknesses of the SARG program. Results The SARG yielded positive outcomes as evidenced by mentee increase in grant submissions, publications, and professional presentations. Focus-group qualitative data highlighted program and institutional barriers as well as successes that surfaced during the program. Based on this evaluation, a Culturally Centered Mentorship Model (CCMM) emerged. Conclusions The CCMM can help counter institutional challenges by valuing culture, community service, and community-based participatory research to support the recruitment and advancement of ethnic minority faculty members in academia.

Culture-Fair Cognitive Ability Assessment: Information Processing and Psychophysiological Approaches.

Valid assessment with diverse populations requires tools that are not influenced by cultural elements. This study investigated the relationships between culture, information processing efficiency, and general cognitive capacities in samples of Caucasian and Mexican American college students. Consistent with the neural efficiency hypothesis, pupillary responses (indexing mental effort) and detection accuracy scores on a visual backward-masking task were both significantly related to the Wechsler Adult Intelligence Scale-Revised (WAIS-R) Full Scale scores. These measures of information processing efficiency were similar in the two groups. However, they were related only to Caucasian American, but not to a comparable sample of Mexican American, students’ WAIS-R scores. Therefore, the differential validity in prediction suggests that the WAIS-R test may contain cultural influences that reduce the validity of the WAIS-R as a measure of cognitive ability for Mexican American students. Information processing and psychophysiological approaches may be helpful in developing culture-fair cognitive ability measures.

Error-rate-related caudate and parietal cortex activation during decision making

&NA; The role of cortical and subcortical structures in processing success or failure in decision‐making situations is unclear. Functional neuroimaging (fMRI) during a two‐choice prediction task was used to investigate the relationship between error‐rate‐related behavioral changes during decision‐making and activation patterns in the caudate and parietal cortex. Success‐related activation was found in caudate and parietal cortex during a two‐choice prediction task. At low error rates, participants utilized success‐related behavioral strategies rate by decreasing switching responses and increasing response predictability, which were associated with activation changes in the caudate and parietal cortex. Therefore, less response switching and increased response predictability during decision making can be directly related to the degree of activation in the caudate and posterior parietal cortex. NeuroReport 14:923–928

Symptoms of depression and cognitive functioning in older American Indians

Depression and lower cognitive functioning are common conditions in older populations. While links between psychopathology and neuropsychological performance have been studied in the white majority population, little is known about such links in the American Indian population. American Indians aged 60 and older (n = 140) completed structured interviews that included a depression screener and two cognitive screening measures, the Mini-Mental State Examination (MMSE) and the Mattis Dementia Rating Scale (MDRS). Participants had mean values of 26.7/30 on the MMSE and 125.8/144 on the MDRS. The depression screen was not associated with the MMSE or MDRS total scores. However, older American Indians who screened positive for depression scored lower than did those American Indians who screened negatively for depression (27.7 versus 29.8 respectively) on the MDRS conceptualization subscale after adjusting for sociodemographic and health variables. The combined effects of psychopathology and cognitive impairment are likely to adversely impact the health and welfare of American Indians and their families. More research is needed to provide a better understanding of the relationship between psychopathology and cognition that will help inform clinical treatment for psychopathology in older ethnic minorities.

Acculturation and Alcohol Treatment in Ethnic Minority Populations: Assessment Issues and Implications

ABSTRACT The roles of culture and ethnicity are crucial for understanding the relevance of personal and social factors involved in the drinking patterns of individuals. Research has shown that acculturative stress is associated with poorer health outcomes and may be linked to problematic drinking. This article briefly outlines issues including the construct of acculturation, measuring acculturation, and understanding the implications that it has with alcohol use in ethnic minorities. A study is presented that illustrates the association between acculturation and drinking patterns in older White and Hispanic veterans. Greater levels of past drinking were associated with more acculturation into the mainstream U.S. society for the Hispanic veterans. For the White veterans, greater levels of past drinking were associated with greater perceived discrimination and less comfort in mainstream U.S. society. Based on the literature, implications for clinical treatment are presented. Clinicians are called upon to understand the worldview of their clients and engage in culturally sensitive alcohol treatments.

Low-level inorganic arsenic exposure and neuropsychological functioning in American Indian elders

Background: Inorganic arsenic at high and prolonged doses is highly neurotoxic. Few studies have evaluated whether long‐term, low‐level arsenic exposure is associated with neuropsychological functioning in adults. Objectives: To investigate the association between long‐term, low‐level inorganic arsenic exposure and neuropsychological functioning among American Indians aged 64–95. Methods: We assessed 928 participants in the Strong Heart Study by using data on arsenic species in urine samples collected at baseline (1989–1991) and results of standardized tests of global cognition, executive functioning, verbal learning and memory, fine motor functioning, and speed of mental processing administered during comprehensive follow‐up evaluations in 2009–2013. We calculated the difference in neuropsychological functioning for a 10% increase in urinary arsenic with adjustment for sex, age, education, and study site. Results: The sum of inorganic and methylated arsenic species (∑As) in urine was associated with limited fine motor functioning and processing speed. A 10% increase in ∑As was associated with a .10 (95% CI −.20, −.01) decrease on the Finger Tapping Test for the dominant hand and a .13 decrease (95% CI −.21, −.04) for the non‐dominant hand. Similarly, a 10% increase in ∑As was associated with a .15 (95% CI −.29, .00) decrease on the Wechsler Adult Intelligence Scale–Fourth Edition Coding Subtest. ∑As was not associated with other neuropsychological functions. Conclusions: Findings indicate an adverse association between increased urinary arsenic fine motor functioning and processing speed, but not with other neuropsychological functioning, among elderly American Indians. HighlightsWe study arsenics effect on neuropsychological health of older American Indians.We assess arsenic from 1991 and neuropsychological test results 20 years later.We find that arsenic exposure lowers fine motor functioning and processing speed.

Ethnicity and Sexual Attitudes Affect Women’s Judgments of Sexual Victimization Risk:

This study evaluated the effects of ethnicity, sexual attitudes, and sexual victimization history on women’s judgments of sexual victimization risk in a set of dating and social scenarios. An ethnically diverse sample of undergraduate women (n = 408) were asked to rate how risky the situations were in terms of having an unwanted sexual experience. American Indian women rated the situations as more risky than did non-Hispanic White or Hispanic women. In addition, participants with more positive attitudes toward a range of sexual experiences rated the situations as less risky than did women with less positive attitudes. Possible implications are discussed.

Left Ventricular Mass, Brain Magnetic Resonance Imaging, and Cognitive Performance: Results From the Strong Heart Study

Left ventricular mass (LVM) has been shown to serve as a measure of target organ damage resulting from chronic exposure to several risk factors. Data on the association of midlife LVM with later cognitive performance are sparse. We studied 721 adults (mean age 56 years at baseline) enrolled in the Strong Heart Study (SHS, 1993–1995) and the ancillary CDCAI (Cerebrovascular Disease and Its Consequences in American Indians) Study (2010–2013), a study population with high prevalence of cardiovascular disease. LVM was assessed with transthoracic echocardiography at baseline in 1993 to 1995. Cranial magnetic resonance imaging and cognitive testing were undertaken between 2010 and 2013. Generalized estimating equations were used to model associations between LVM and later imaging and cognition outcomes. The mean follow-up period was 17 years. A difference of 25 g in higher LVM was associated with marginally lower hippocampal volume (0.01%; 95% confidence interval, 0.02–0.00; P=0.001) and higher white matter grade (0.10; 95% confidence interval, 0.02–0.18; P=0.014). Functionally, participants with higher LVM tended to have slightly lower scores on the modified mini-mental state examination (0.58; 95% confidence interval, 1.08–0.08; P=0.024). The main results persisted after adjusting for blood pressure levels or vascular disease. The small overall effect sizes are partly explained by survival bias because of the high prevalence of cardiovascular disease in our population. Our findings emphasize the role of cardiovascular health in midlife as a target for the prevention of deleterious cognitive and functional outcomes in later life.