Cognitive Performance Across the Life Course of Bolivian Forager-Farmers With Limited Schooling

Cognitive performance is characterized by at least two distinct life course trajectories. Many cognitive abilities (e.g. “effortful processing” abilities including fluid reasoning, and processing speed) improve throughout early adolescence and start declining in early adulthood, while other abilities (e.g. “crystallized” abilities like vocabulary breadth) improve throughout adult life, remaining robust even at late ages. Although schooling may impact performance and cognitive “reserve”, it has been argued that these age patterns of cognitive performance are human universals. Here we examine age patterns of cognitive performance among Tsimane forager-horticulturalists of Bolivia, and test whether schooling is related to differences in cognitive performance over the life course to assess models of active vs. passive cognitive reserve. We used a battery of eight tasks to assess a range of latent cognitive traits reflecting attention, processing speed, verbal declarative memory and semantic fluency (n=919 individuals, 49.9% female). Tsimane cognitive abilities show similar age-related differences as observed in industrialized populations: higher throughout adolescence and only slightly lower in later adulthood for semantic fluency, but substantially lower performance beginning in early adulthood for all other abilities. Schooling is associated with greater cognitive abilities at all ages controlling for sex, but has no attenuating effect on cognitive performance in late adulthood, consistent with models of passive cognitive reserve. We interpret the minimal attenuation of semantic fluency late in life in light of evolutionary theories of post-reproductive lifespan, which emphasize indirect fitness contributions of older adults through the transfer of information, labor and food to descendant kin

Sexual Selection for Indicators of Intelligence : the Role of Vocabulary in Human Courtship

Color poster with text, images, and graphs.Numerous lines of research have affirmed the link between verbal ability and intelligence (Weschler, 1958). Therefore, it is highly likely that breadth of vocabulary serves as a phenotypic proxy for intelligence. Previous research in this area has indicated that priming individuals with mating cues results in higher levels of creativity (Griskevicius, Cialdini, & Kenrick, 2006) and increases in the use of low-frequency words (Rosenburg & Tunney, 2008) on writing tasks. However, none of this work has examined the effect of mating cues in spoken verbal communication situations. Thus, the current study is the first of its kind to explore the effect of mating primes on an individual's use of vocabulary in oral communication.University of Wisconsin--Eau Claire Office of Research and Sponsored Program

Again the Stallu Come : the Role of Folklore in the Resurgence of Traditional Sami Culture

Color poster with text and photographs.Traditional Sami tales represent a rich history of storytelling and interpretation of the natural phenomena that surrounded the early inhabitants of northern Scandinavia. As such, they were a prized focus for restoration as the Sami language became successfully adapted to print and the first authors of Sami poetry and literature were able to share their writings with the world. The current study presents an interpretation and report of data collected during a two and a half month experience in the field and an account of the role that a small community of Norwegian Sami has continued to play in the revival of local traditional culture.University of Wisconsin--Eau Claire Office of Research and Sponsored Program

25 Years of GRE Scores and Graduate Enrollments by Discipline, Sex, and Ethnicity

Color poster with text and graphs.The Graduate Record Examination (GRE) is a highstakes test of developed cognitive abilities. Undergraduate students who aspire to graduate school are often recommended and sometimes required to take the GRE, or a test like it such as the LSAT or MCAT, for admission. Several lines of research have established these tools as valid measures of cognitive ability and strong predictors of subsequent success. In this study, data was compiled to determine how scores on the GRE have fared over time. Comparisons were made of GRE scores and graduate enrollment patterns by sex, ethnicity, and discipline to explore the flow of intellectual talent into graduate education.University of Wisconsin--Eau Claire Office of Research and Sponsored Program

Scientific Literacy and its Correlates : Knowledge of Evolution, Genetics, and the Physical Sciences in UWEC Freshmen

Color poster with text, graphs, and tables.Rates of basic scientific literacy in adult America are low--in fact, they are lower than rates of scientific literacy in 32 European countries and Japan. Researchrs have identified education as a key positive correlate, and religiosity as a key negative correlate, of scientific literacy. However, no study has tracked the same individuals over time to determine whether undergoing a college education is followed by growth in scientific literacy and, if so, the degree to which incoming level of religiousity and exposure to science coursework moderate that growth. In this poster, we describe the results of Phase I of a planned longitudinal study of UWEC students' scientific literacy.University of Wisconsin--Eau Claire Office of Research and Sponsored Program

Expectations of the Future : Undergraduates' Plans for Work, Love, and Family

Black and white poster with text and graphs.In this poster we describe the results of Phase I of a planned three year longitudinal study. During the 2009-2010 academic year, we collected responses from 344 underclassmen enrolled in a 100-level general education course. In addition to measures of their mating orientations and mate preferences, students reported on a variety of plans for the future (as applicable): age of anticipated marriage and child rearing, number of children desired, desired salary and education, and work plans before and after children. We describe men?s and women?s responses to these measures and speculate how response patterns might differ when we assess them in three years.University of Wisconsin--Eau Claire Office of Research and Sponsored Program

Universal quenching of common fluorescent probes by water and alcohols

Although biological imaging is mostly performed in aqueous media, it is hardly ever considered that water acts as a classic fluorescence quencher for organic fluorophores. By investigating the fluorescence properties of 42 common organic fluorophores recommended for biological labelling, we demonstrate that H2O reduces their fluorescence quantum yield and lifetime by up to threefold and uncover the underlying fluorescence quenching mechanism. We show that the quenching efficiency is significantly larger for red-emitting probes and follows an energy gap law. The fluorescence quenching finds its origin in high-energy vibrations of the solvent (OH groups), as methanol and other linear alcohols are also found to quench the emission, whereas it is restored in deuterated solvents. Our observations are consistent with a mechanism by which the electronic excitation of the fluorophore is resonantly transferred to overtones and combination transitions of high-frequency vibrational stretching modes of the solvent through space and not through hydrogen bonds. Insight into this solvent-assisted quenching mechanism opens the door to the rational design of brighter fluorescent probes by offering a justification for protecting organic fluorophores from the solvent via encapsulation

Ultrafast Photoinduced Charge Separation in Naphthalene Diimide Based Multichromophoric Systems in Liquid Solutions and in a Lipid Membrane

The photophysical properties of multichromophoric systems consisting of eight red or blue naphthalene diimides (NDIs) covalently attached to a p-octiphenyl scaffold, as well as a blue bichromophoric system with a biphenyl scaffold, have been investigated in detail using femtosecond time-resolved spectroscopy. The blue octachromophoric systems have been recently shown to self-assemble as supramolecular tetramers in lipid bilayer membranes and to enable generation of a transmembrane proton gradient upon photoexcitation (Bhosale, S.; Sisson, A. L.; Talukdar, P.; Fürstenberg, A.; Banerji, N.; Vauthey, E.; Bollot, G.; Mareda, J.; Röger, C.; Würthner, F.; Sakai, N.; Matile, S. Science 2006, 313, 84). A strong reduction of the fluorescence quantum yield was observed when going from the single NDI units to the multichromophoric systems in methanol, the effect being even stronger in a vesicular lipid membrane. Fluorescence up-conversion measurements reveal ultrafast self-quenching in the multichromophoric systems, whereas the formation of the NDI radical anion, evidenced by transient absorption measurements, points to the occurrence of photoinduced charge separation. The location of the positive charge could not be established unambiguously from the transient absorption measurements, but energetic considerations indicate that charge separation should occur between two NDI units in the blue systems, whereas both an NDI unit and the p-octiphenyl scaffold could act as electron donor in the red system. The lifetime of the charge-separated state was found to increase from 22 to 45 ps by going from the bi- to the octachromophoric blue systems in methanol, while a 400 ps decay component was observed in the lipid membrane. This lifetime lengthening is explained in terms of charge migration that is most efficient when the octachromophoric systems are assembled as supramolecular tetramers in the lipid membrane. Furthermore, the average charge-separated state lifetime of the red system in methanol is even larger and amounts to 750 ps. This effect cannot be simply explained in terms of Marcus inverted regime as the driving force for charge recombination in the red system is only slightly larger than in the blue one. A better spatial separation of the charges in the red system stemming from the localization of the hole on the p-octiphenyl scaffold could additionally contribute to the slowing down of charge recombination

Cognitive Performance Across the Life Course of Bolivian Forager-Farmers With Limited Schooling

Cognitive performance is characterized by at least two distinct life course trajectories. Many cognitive abilities (e.g., “effortful processing” abilities, including fluid reasoning and processing speed) improve throughout early adolescence and start declining in early adulthood, whereas other abilities (e.g., “crystallized” abilities like vocabulary breadth) improve throughout adult life, remaining robust even at late ages. Although schooling may impact performance and cognitive “reserve,” it has been argued that these age patterns of cognitive performance are human universals. Here we examine age patterns of cognitive performance among Tsimane forager-horticulturalists of Bolivia and test whether schooling is related to differences in cognitive performance over the life course to assess models of active versus passive cognitive reserve. We used a battery of eight tasks to assess a range of latent cognitive traits reflecting attention, processing speed, verbal declarative memory, and semantic fluency (n 919 individuals, 49.9% female). Tsimane cognitive abilities show similar age-related differences as observed in industrialized populations: higher throughout adolescence and only slightly lower in later adulthood for semantic fluency but substantially lower performance beginning in early adulthood for all other abilities. Schooling is associated with greater cognitive abilities at all ages controlling for sex but has no attenuating effect on cognitive performance in late adulthood, consistent with models of passive cognitive reserve. We interpret the minimal attenuation of semantic fluency late in life in light of evolutionary theories of postreproductive life span, which emphasize indirect fitness contributions of older adults through the transfer of information, labor, and food to descendant kin