Gadd45b knockout mice exhibit selective deficits in hippocampus-dependent long-term memory

Growth arrest and DNA damage-inducible β (Gadd45b) has been shown to be involved in DNA demethylation and may be important for cognitive processes. Gadd45b is abnormally expressed in subjects with autism and psychosis, two disorders associated with cognitive deficits. Furthermore, several high-throughput screens have identified Gadd45b as a candidate plasticity-related gene. However, a direct demonstration of a link between Gadd45b and memory has not been established. The current studies first determined whether expression of the Gadd45 family of genes was affected by contextual fear conditioning. Gadd45b, and to a lesser extent Gadd45g, were up-regulated in the hippocampus following contextual fear conditioning, whereas Gadd45a was not. Next, Gadd45b knockout mice were tested for contextual and cued fear conditioning. Gadd45b knockout mice exhibited a significant deficit in long-term contextual fear conditioning; however, they displayed normal levels of short-term contextual fear conditioning. No differences between Gadd45b knockout and wild-type mice were observed in cued fear conditioning. Because cued fear conditioning is hippocampus independent, while contextual fear conditioning is hippocampus dependent, the current studies suggest that Gadd45b may be important for long-term hippocampus-dependent memory storage. Therefore, Gadd45b may be a novel therapeutic target for the cognitive deficits associated with many neurodevelopmental, neurological, and psychiatric disorders.     

Executive function on the Psychology Experiment Building Language tests

The measurement of executive function has a long history in clinical and experimental neuropsychology. The goal of the present report was to determine the profile of behavior across the lifespan on four computerized measures of executive function contained in the recently developed Psychology Experiment Building Language (PEBL) test battery and evaluate whether this pattern is comparable to data previously obtained with the non-PEBL versions of these tests. Participants (N = 1,223; ages, 5–89 years) completed the PEBL Trail Making Test (pTMT), the Wisconsin Card Sort Test (pWCST; Berg, Journal of General Psychology, 39, 15–22, 1948; Grant & Berg, Journal of Experimental Psychology, 38, 404–411, 1948), the Tower of London (pToL), or a time estimation task (Time-Wall). Age-related effects were found over all four tests, especially as age increased from young childhood through adulthood. For several tests and measures (including pToL and pTMT), age-related slowing was found as age increased in adulthood. Together, these findings indicate that the PEBL tests provide valid and versatile new research tools for measuring executive functions.     

Four models of the functional contribution of mirror systems

In this paper we raise three questions of clarification about Alfred Mele's fine recent book, Free Will and Luck. Our questions concern the following topics: (i) Mele's combination of ‘luck’ and ‘Frankfurt-style’ objections to libertarianism, (ii) Mele's stipulations about ‘compatibilism’ and the relation between questions about free action and questions about moral responsibility, and (iii) Mele's treatment of the Consequence Argument.     

Immigration Opposition Among U.S. Whites: General Ethnocentrism or Media Priming of Attitudes About Latinos?

General ethnocentrism seems to be a powerful antecedent of immigration opinion, typically displaying larger effects than economic concerns. News about immigration, however, may focus attention on a particular group in a given historical moment. We predict group‐specific affect, not general ethnocentrism, should most powerfully shape immigration policy opinion in the contemporary United States. We test this expectation with content analyses of news coverage, survey data from 1992 to 2008, a survey experiment, and official statistics. First, we find that mentions of Latinos in news coverage of immigration outpace mentions of other groups beginning in 1994, the year when Proposition 187, a proposal in California to end most social welfare and educational assistance to illegal immigrants, garnered significant national attention. Second, while ethnocentrism dominates economic concerns in explanations of Whites' immigration policy opinions, attitudes toward Latinos in particular account for nearly all of the impact of ethnocentrism since 1994. Finally, journalistic attention to Latino immigration roughly parallels actual rates of immigration from Latin America, suggesting the media shaping of policy opinion around this group may be driven by real‐world demographic patterns.     

Projecting Earth on to Heaven: The Hopes of Frank Drake and the Fears of Stephen Hawking

Space scientists today exemplify the projection theory of religion, only they substitute space aliens for the Heavenly Father. Projections are delusions, not facts.     

Naturalisms: Scientific? Religious? Theological?

Is nature all there is? Or, is there more? If nature is the only reality, is it ultimate or sacred? Differing answers to these questions determine the different brands of naturalism on the religious shelf. What virtually all of today’s naturalists agree on is this: science provides the means for revealing reality, the sole reality which is material, physical, and cosmic. Naturalists also agree that supranaturalism should be rejected. What naturalists differ on whether nature is divine or not. This article sorts out the issues and differing positions taken on each issue. The author contends that a post-Newtonian worldview remains open to a concept of God wherein divine action in nature’s world influences creativity and transformation.     

Effect of Representational Distance Between Meanings on Recognition of Ambiguous Spoken Words

Previous research indicates that mental representations of word meanings are distributed along both semantic and syntactic dimensions such that nouns and verbs are relatively distinct from one another. Two experiments examined the effect of representational distance between meanings on recognition of ambiguous spoken words by comparing recognition of unambiguous words, noun–verb homonyms, and noun–noun homonyms. In Experiment 1, auditory lexical decision was fastest for unambiguous words, slower for noun–verb homonyms, and slowest for noun–noun homonyms. In Experiment 2, response times for matching spoken words to pictures followed the same pattern and eye fixation time courses revealed converging, gradual time course differences between conditions. These results indicate greater competition between meanings of ambiguous words when the meanings are from the same grammatical class (noun–noun homonyms) than when they are from different grammatical classes (noun–verb homonyms).