Semantic-memory sources of episodic retrieval failure

In a cued-recall paradigm, retrieval blocking was investigated as a source of episodic retrieval failure. Each unrelated-interference (UR-I) word pair (e.g., “nurse-dollar”) had its own “competitive alternative” (e.g., “doctor’), which not only was strongly related to the cue word, but also possessed the same first two letters and final letter as did the target word. None of the unrelated-control (UR-C) word pairs (e.g., “clock-dollar”) had such an alternative. Cued recall substantially increased from the cue-word-only (e.g., “nurse- ”) to the three-letters-also cue condition (e.g., “nurse-do___r”) for the UR-C but not for the UR-I word pairs. Instead, subjects frequently reported the competitive alternatives in place of the UR-I target words in the three-letters-also cue condition. It was suggested that, relying on the primary plausibility judgment, subjects falsely accepted the competitive alternatives while the UR-I target words were blocked from retrieval by the potent retrieval of these plausible alternatives.     

"Robovie, you'll have to go into the closet now": children's social and moral relationships with a humanoid robot

Children will increasingly come of age with personified robots and potentially form social and even moral relationships with them. What will such relationships look like? To address this question, 90 children (9-, 12-, and 15-year-olds) initially interacted with a humanoid robot, Robovie, in 15-min sessions. Each session ended when an experimenter interrupted Robovie's turn at a game and, against Robovie's stated objections, put Robovie into a closet. Each child was then engaged in a 50-min structural-developmental interview. Results showed that during the interaction sessions, all of the children engaged in physical and verbal social behaviors with Robovie. The interview data showed that the majority of children believed that Robovie had mental states (e.g., was intelligent and had feelings) and was a social being (e.g., could be a friend, offer comfort, and be trusted with secrets). In terms of Robovie's moral standing, children believed that Robovie deserved fair treatment and should not be harmed psychologically but did not believe that Robovie was entitled to its own liberty (Robovie could be bought and sold) or civil rights (in terms of voting rights and deserving compensation for work performed). Developmentally, while more than half the 15-year-olds conceptualized Robovie as a mental, social, and partly moral other, they did so to a lesser degree than the 9- and 12-year-olds. Discussion focuses on how (a) children's social and moral relationships with future personified robots may well be substantial and meaningful and (b) personified robots of the future may emerge as a unique ontological category.     

Context-dependent olfactory learning monitored by activities of salivary neurons in cockroaches

Context-dependent discrimination learning, a sophisticated form of nonelemental associative learning, has been found in many animals, including insects. The major purpose of this research is to establish a method for monitoring this form of nonelemental learning in rigidly restrained insects for investigation of underlying neural mechanisms. We report context-dependent olfactory learning (occasion-setting problem solving) of salivation, which can be monitored as activity changes of salivary neurons in immobilized cockroaches, Periplaneta americana. A group of cockroaches was trained to associate peppermint odor (conditioned stimulus, CS) with sucrose solution reward (unconditioned stimulus, US) while vanilla odor was presented alone without pairing with the US under a flickering light condition (1.0 Hz) and also trained to associate vanilla odor with sucrose reward while peppermint odor was presented alone under a steady light condition. After training, the responses of salivary neurons to the rewarded peppermint odor were significantly greater than those to the unrewarded vanilla odor under steady illumination and those to the rewarded vanilla odor was significantly greater than those to the unrewarded peppermint odor in the presence of flickering light. Similar context-dependent responses were observed in another group of cockroaches trained with the opposite stimulus arrangement. This study demonstrates context-dependent olfactory learning of salivation for the first time in any vertebrate and invertebrate species, which can be monitored by activity changes of salivary neurons in restrained cockroaches.     

Perception of the end position of a limb loaded with a weight

We examined the effect of loading a weight on the perception of the end position of the limb. The participants haptically perceived where the end of their limb was located while they swung the limb or statically held it. The results showed that the loading of a weight influenced participants' perception only when they swung the limb; when the weight was attached to a participant's hand, the position was perceived to be farther from the body than when the weight was attached to the forearm or no weight was attached. We also found that the end position was generally underestimated when the participants swung their limb. On the other hand, when the participants statically held their limb, the perceived position was not affected by the loading of the weight and was rather precise. These results suggest that the perceptual system for limb end position is sensitive to changes in the surrounding haptic information caused by moving the limb.     

Poverty,ethnicity, and risk of obesity among low birth weight infants

The independent and joint effects of family and neighborhood poverty and ethnicity upon weight trajectories from age two to six-and-a-half were examined using data from the Infant Health and Development Program (N = 985), an early intervention program for low birth weight children and families. At age two, family poverty was associated with higher body mass index (BMI), whereas neighborhood poverty and ethnicity were not. Over time, the BMI of toddlers from poor and near poor neighborhoods increased nonlinearly, while those from nonpoor neighborhoods remained stable. BMIs of Hispanic-American toddlers increased steadily over time, unlike African-American and Anglo-American toddlers. Although initially similar, over time African-American toddlers' BMIs increased more rapidly than Anglo-American toddlers. Family and neighborhood poverty and ethnicity were associated with BMI. More work is needed on how poverty and ethnicity contribute to differences in early weight gain in conjunction with sociocultural and environmental factors in the home and community.     

American-Japanese cultural differences in judgements of emotional expressions of different intensities

Although research has generated a wealth of information on cultural influences on emotion judgements, the information we have to date is limited in several ways. This study extends this literature in two ways, first by obtaining judgements from people in two cultures of expressions portrayed at different intensity levels, and second by incorporating individual level measures of culture to examine their contribution to observed differences. When judging emotion categories in low intensity expressions, American and Japanese judges see the emotion intended at above-chance rates, albeit lower than when judging high intensity faces. Also, American and Japanese intensity ratings of external displays and internal experiences differ dramatically for low intensity expressions compared to high intensity faces. Finally, the two cultural dimensions measured in this study—individualism versus collectivism (IC) and status differentiation (SD)—accounted for almost all of the variance in the observed differences. These findings are discussed in terms of their underlying possible mechanisms, and future research possibilities.     

In-situ high-voltage electron microscopy observations of reactions between molten Zn and Fe

Reactions between molten Zn and Fe have been observed directly by means of an in-situ heating experiment in a high-voltage electron microscope. In order to suppress evaporation of Zn during the in-situ heating experiment the specimen was coated with a plasma-polymerized hydrocarbon film. Mechanisms for the formation of Fe-Zn intermetallic compounds are discussed and it is concluded that all the models proposed so far are of doubtful validity.     

Motor Learning as a Function of KR Schedule and Characteristics of Task-Intrinsic Feedback

Forty participants (age range = 18–35 years) practiced 1 of 2 versions of an aiming task (with or without spring resistance). Knowledge of results (KR) was provided to them either immediately or after a delay of 2 trials. Immediate KR led to significantly more accurate performance during the 80 trials in acquisition but significantly less accurate performance on a 40-trial retention test given 24 hr after practice. In addition, the spring version of the task was performed significantly less accurately than the no-spring version on the 24-hr retention test. Most important, a significant interaction on the 24-hr retention test revealed that performance of the no-spring version of the task, when KR had been given after a 2-trial delay, was significantly more accurate than performance of the other 3 combinations of task version and KR schedule. The results suggest that KR dependency in motor skill learning is related to familiarity with task-intrinsic feedback in addition to the schedule on which KR is presented.     

Nociceptin and its metabolite attenuate U0126-induced memory impairment through a nociceptin opioid peptide (NOP) receptor-independent mechanism

Nociceptin binds to nociceptin opioid peptide (NOP) receptors. We reported that although high doses of nociceptin impaired memory function and that these effects were mediated via NOP receptors, low doses of nociceptin attenuated the memory impairment, and these attenuating effects were not mediated via NOP receptors. Even very low doses of nociceptin were biologically active and suggested a certain binding site for this peptide, but the mechanism underlying this attenuating effect has not yet been elucidated. In the present study, we investigated the effect of an intrahippocampal injection (i.h.) of nociceptin on memory impairment induced by U0126, a MEK inhibitor, and Rp-cAMPS, a PKA inhibitor in a step-down type passive avoidance test. U0126 (2.63 nmol/mouse, i.h.) impaired memory formation and training-dependent phosphorylation of ERK2 in the hippocampus. Co-administration of nociceptin (10 fmol/mouse) significantly attenuated memory impairment, while it did not attenuate the inhibition of training-dependent phosphorylation of ERK2 induced by U0126. On the other hand, nociceptin did not attenuate memory impairment induced by Rp-cAMPS (0.448 nmol/mouse, i.h.). Nociceptin (1 fmol/mouse) also attenuated U0126 (5.26 nmol/mouse)-induced memory impairment in NOP receptor knockout mice. Nociceptin was reported to metabolize into fragments (1–13) and (14–17) in vivo, which showed pharmacological activities without affecting NOP receptors. Our findings showed that nociceptin (14–17) (1 fmol/mouse) also attenuated U0126-induced memory impairment, while nociceptin (1–13) (0.1–10 fmol/mouse) did not attenuate memory impairment. These results suggest a novel action site or mechanism for the attenuating effects of nociceptin and its metabolite, and the sequence of nociceptin (14–17) is a critical structure.     

Importance of crack-propagation-induced ε-martensite in strain-controlled low-cycle fatigue of high-Mn austenitic steel

We investigated the roles of deformation-induced ε-martensitic transformation on strain-controlled low-cycle fatigue (LCF) through crack-propagation analysis involving a notching technique that used a focused ion beam (FIB) setup on Fe–30Mn–4Si–2Al austenitic steel. Using the FIB notch, we separated the microstructure evolution into macroscopic cyclic deformation-induced and crack-propagation-induced microstructures. Following this, we clarified the fatigue crack-propagation-induced ε-martensitic transformation to decelerate crack propagation at a total strain range of 2%, obtaining an extraordinary LCF life of 1.1 × 10⁴ cycles.