Massed and spaced learning in honeybees: the role of CS, US, the intertrial interval, and the test interval

Conditioning the proboscis extension reflex of harnessed honeybees (Apis mellifera) is used to study the effect temporal spacing between successive conditioning trials has on memory. Retention is monitored at two long-term intervals corresponding to early (1 and 2 d after conditioning) and late long-term memory (3 and 4 d). The acquisition level is varied by using different conditioned stimuli (odors, mechanical stimulation, and temperature increase at the antenna), varying strengths of the unconditioned stimulus (sucrose), and various numbers of conditioning trials. How learning trials are spaced is the dominant factor both for acquisition and retention, and although longer intertrial intervals lead to better acquisition and higher retention, the level of acquisition per se does not determine the spacing effect on retention. Rather, spaced conditioning leads to higher memory consolidation both during acquisition and later, between the early and long-term memory phases. These consolidation processes can be selectively inhibited by blocking protein synthesis during acquisition.     

Risk-Taking and Smoking Tendency Among Primarily African American School Children: Moderating Influences of Peer Susceptibility

We examined the hypothesis that peer susceptibility would moderate the association between risk-taking and tendency to smoke in adolescents who were primarily African American. Participants were 88 preadolescents recruited from a 6th grade classroom in a public elementary school. We found an interaction of risk-taking and susceptibility to peer influence on smoking tendency. Specifically, a moderator effect was found for peer influence on the association between risk-taking and smoking tendency. The importance of examining peer susceptibility on health promotion and other health behaviors in children and adolescents was supported.     

A domain‐specific risk‐attitude scale: measuring risk perceptions and risk behaviors

We present a psychometric scale that assesses risk taking in five content domains: financial decisions (separately for investing versus gambling), health/safety, recreational, ethical, and social decisions. Respondents rate the likelihood that they would engage in domain‐specific risky activities (Part I). An optional Part II assesses respondents' perceptions of the magnitude of the risks and expected benefits of the activities judged in Part I. The scale's construct validity and consistency is evaluated for a sample of American undergraduate students. As expected, respondents' degree of risk taking was highly domain‐specific, i.e. not consistently risk‐averse or consistently risk‐seeking across all content domains. Women appeared to be more risk‐averse in all domains except social risk. A regression of risk taking (likelihood of engaging in the risky activity) on expected benefits and perceived risks suggests that gender and content domain differences in apparent risk taking are associated with differences in the perception of the activities' benefits and risk, rather than with differences in attitude towards perceived risk. Copyright © 2002 John Wiley & Sons, Ltd.     

RPE-based zone of normality for use in evaluating graded exercise test responses in women

The purposes of this study were to identify a zone of normality based upon ratings of perceived exertion (RPE) and compare the RPE of women with coronary artery disease to this zone. 45 healthy women (34.8 +/- 9.1 yr.) completed a Bruce treadmill test. RPE were estimated during the last minute of each workload. The zone of normality was established as the 95% confidence interval spanning the average line when RPE was regressed against MET. 51 women (66.6 +/- 9.3 yr.) with coronary artery disease completed a symptom-limited treadmill test. 31 of the women with coronary artery disease were taking beta blockers. RPE were compared to the RPE/MET relation of the zone. 57% of the women with coronary artery disease estimated RPE above the zone during the treadmill test. RPE responses above the zone of normality indicate an elevated perceptual strain for a given energy expenditure (i.e., MET). The zone of normality might be used as an aid in discriminating between normal and abnormal RPE responses during graded treadmill tests by women with coronary artery disease.     

Distinct single but not necessarily repeated tetanization is required to induce hippocampal late-LTP in the rat CA1

The protein synthesis-dependent form of hippocampal long-term potentiation (late-LTP) is thought to underlie memory. Its induction requires a distinct stimulation strength, and the common opinion is that only repeated tetani result in late-LTP whereas as single tetanus only reveals a transient early-LTP. Properties of LTP induction were compared to learning processes where repetition is often the prerequisite for a long-lasting memory. However, also single events can lead to manifested memory. If LTP subserves processes of learning, similar results should be detectable for LTP. Here we show that a single tetanus is sufficient to induce late-LTP requiring dopaminergic co-transmission during induction.     

The 'hard problem' and the quantum physicists. Part 2: Modern times

This is the second part of a review of the work of quantum physicists on the 'hard part' of the problem of mind. After an introduction which sets the scene and a brief review of contemporary work on the neural correlates of consciousness (NCC) the work of four prominent modern investigators is examined: J.C. Eccles/Friedrich Beck; Henry Stapp; Stuart Hameroff/Roger Penrose; David Bohm. With the exception of David Bohm, all attempt to show where in the brain's microstructure quantum affects could make themselves felt. It is reluctantly concluded that none have neurobiological plausibility. They are all instances, to paraphrase T.H. Huxley, of a beautiful hypothesis destroyed by ugly facts. David Bohm does not attempt to fit his new quantum physics to contemporary neurobiology but instead asks for a radical rethink of our conventional scientific paradigm. He suggests that we should look towards developing a 'pan-experientialism' or 'dual-aspect monism' where consciousness goes 'all the way down' and that the 'hard problem' is not soluble within the framework of ideas provided by 'classical' natural science.     

More Than Just IQ: School Achievement Is Predicted by Self-Perceived Abilities—But for Genetic Rather Than Environmental Reasons

ABSTRACT— Evidence suggests that children's self-perceptions of their abilities predict their school achievement even after one accounts for their tested cognitive ability (IQ). However, the roles of nature and nurture in the association between school achievement and self-perceived abilities (SPAs), independent of IQ, is unknown. Here we reveal that there are substantial genetic influences on SPAs and that there is genetic covariance between SPAs and achievement independent of IQ. Although it has been assumed that the origins of SPAs are environmental, this first genetic analysis of SPAs yielded a heritability of 51% in a sample of 3,785 pairs of twins, whereas shared environment accounted for only 2% of the variance in SPAs. Moreover, multivariate genetic analyses indicated that SPAs predict school achievement independently of IQ for genetic rather than environmental reasons. It should therefore be possible to identify "SPA genes" that predict school achievement independently of "IQ genes."     

BOLD activation varies parametrically with corner angle throughout human retinotopic cortex

The Alternating Brightness Star (ABS) is an illusion that provides insight into the relationship between brightness perception and corner angle. Recent psychophysical studies of this illusion have shown that corner salience varies parametrically with corner angle, with sharp angles leading to strong illusory percepts and shallow angles leading to weak percepts. It is hypothesized that the illusory effects arise because of an interaction between surface corners and the shape of visual receptive fields: sharp surface corners may create hotspots of high local contrast due to processing by center-surround and other early receptive fields. If this hypothesis is correct, early visual neurons should respond powerfully to sharp corners and curved portions of surface edges. Indeed, the primary role of early visual neurons may be to localize the discontinuities along the edges of surfaces. If so, all early visual areas should show greater BOLD responses to sharp corners than to shallow corners. On the other hand, if corner processing is exclusively constrained to certain areas of the brain, only those specific areas will show greater responses to sharp vs shallow corners. To address this we explored the BOLD correlates of the ABS illusion in the human visual cortex using fMRI. We found that BOLD signal varies parametrically with corner angle throughout the visual cortex, offering the first neurophysiological correlates of the ABS illusion. This finding provides a neurophysiological basis for the previously reported psychophysical data that showed that corner salience varied parametrically with corner angle. We propose that all early visual areas localize discontinuities along the edges of surfaces, and that specific cortical corner-processing circuits further establish the specific nature of those discontinuities, such as their orientation.     

Special Topics in the Journal of Counseling & Development,Volumes 66–80

The authors review previous examinations of the American Counseling Association's (ACA) Journal of Counseling & Development (JCD), consider various editors' policies that shaped the Journal, and update L. W. Harmon and H. E. Harker's (1989) analysis of special interest topics featured in JCD. Studying the flagship professional journal of ACA provides insight into the evolution and development of the profession of counseling.     

Lateralized cognition: asymmetrical and complementary strategies of pigeons during discrimination of the "human concept"

This study was aimed at revealing which cognitive processes are lateralized in visual categorizations of "humans" by pigeons. To this end, pigeons were trained to categorize pictures of humans and then tested binocularly or monocularly (left or right eye) on the learned categorization and for transfer to novel exemplars (Experiment 1). Subsequent tests examined whether they relied on memorized features or on a conceptual strategy, using stimuli composed of new combinations of familiar and novel humans and backgrounds (Experiment 2), whether the hemispheres processed global or local information, using pictures with different levels of scrambling (Experiment 3), and whether they attended to configuration, using distorted human figures (Experiment 4). The results suggest that the left hemisphere employs a category strategy and concentrates on local features, while the right hemisphere uses an exemplar strategy and relies on configuration. These cognitive dichotomies of the cerebral hemispheres are largely shared by humans, suggesting that lateralized cognitive systems already defined the neural architecture of the common ancestor of birds and mammals.