Conditioned taste aversion with sucrose and tactile stimuli in the pond snail Lymnaea stagnalis

A new form of taste aversion conditioning was established in the pond snail Lymnaea stagnalis. An associative memory, lasting 24h, was produced in the pond snail with 20 pairings of 100 mM sucrose as the conditioned stimulus (CS) and mechanical stimulation to the head as the unconditioned stimulus (UCS). Animals exposed to reverse pairings of the CS and UCS failed to learn the association. The learning was characterized by a shift in the response to the UCS from a whole-body withdrawal response to the cessation of feeding behavior.     

Age differences in the effect of physical activity on depressive symptoms

This study examined associations between physical activity and depressive symptoms in 1,151 community-dwelling adults in Japan. Physical activity was measured using a pedometer, whereas depressive symptoms were assessed with the Center for Epidemiological Studies-Depression Scale. A structural equation modeling with a cross-lagged panel design revealed that for the older adults (65-79 years of age), daily walking at baseline predicted fewer depressive symptoms at the 2-year follow-up, even after adjusting for confounders. In contrast, the association was not confirmed for the middle-aged adults (40-64 years of age). Findings suggest that age should be considered when estimating the effect of physical activity on psychological well-being.     

What does the dominant eye dominate? A brief and somewhat contentious review

We examine a set of implicit and explicit claims about the concept of eye dominance that have been made over the years and note that the new literature on eye dominance does not reflect the old literature from the first half of the last century. We argue that the visual and oculomotor function of the dominant eye--defined by such criteria as asymmetry in acuity, rivalry, or sighting--remains unknown and that the usefulness of the concept for understanding its function is yet to be determined. We suggest that the sighting-dominant eye is the eye used for monocular tasks and has no unique functional role in vision.     

An ERP study of sensory mismatch expressions in Japanese

Combinations of different sensory words produce mismatch expressions like smooth color and red touch in contrast to normal expressions like red color and smooth touch. Concerning these sensory mismatch expressions, results of three experiments are reported. Experiment 1 revealed that (i) mismatch expressions were less comprehensible than normal expressions, and that (ii) there were two patterns among mismatch expressions: the high-comprehensible mismatch expression (HighCME, e.g., smooth color) and the low-comprehensible mismatch expression (LowCME, e.g., red touch). Experiment 2 revealed that the mismatch expressions produced a significantly greater N400 amplitude than the normal expressions. Experiment 3 implied that the difference between High/LowCME was reflected in a later latency band or in a topographical difference of N400, although the statistical significance was marginal. It is argued that the processes to integrate linguistic elements (e.g., combining adjectives and nouns) are not homogeneous.     

Facilitation of Sodium Aversion Learning in Sodium-Deprived Rats

Two experiments with rats explored the effects of sodium deprivation induced by furosemide injections upon acquisition of taste aversion to sodium chloride (NaCl). In Experiment 1, rats under either sodium deprivation or a balanced nutrition condition were given access to a limited amount of NaCl solution prior to poisoning. When all rats were tested under sodium repletion, the previously sodium-deprived rats consumed less NaCl than did the nondeprived rats. This finding was replicated in Experiment 2A in which ingestion of a compound solution of NaCl and hydrochloric acid (HCl) was followed by poisoning. Consumption of HCl, however, showed the opposite pattern: the sodium-deprived rats drank more HCl than did the nondeprived rats, a result that was replicated in Experiment 2B. These results suggest that sodium deprivation strengthens the salience of NaCl, thereby facilitating acquisition of aversion to this taste and strongly overshadowing that to a simultaneously presented taste.     

Visual evoked potentials to the geometric forms in the randomized presentation

Two outlined geometric figures, an equilateral triangle and a circle, of equal contour length, were randomly presented at a fixed position in the lower or upper part of the visual field (LVF and UVF). Transient visual evoked potentials (VEPs) were recorded monopolarly from the inion (I), 5, 10, 15 cm above it (I5, I10, I15) and Fz, for 12 subjects. Grand-averaged VEPs were computed. A negative (N) wave (averaged peak latency 155 ms) was identified in the LVF and a positive (P) wave (130 ms) in the UVF. In the LVF, the N amplitude of the triangle was significantly larger than that of the circle at I5 and I. Regarding the P wave in the UVF, the triangle was of a significantly longer latency than the circle at I15, I10 and I5. The enhancement of the N amplitude for the triangle in the LVF is not attributable to the arousal caused by the preparatory state for the figure, since the subject could not predict the figure to be presented next or its position.     

Estimation of height for persons in pictures

We report three experiments in which subjects estimated the height of persons seen in pictures. In Experiment 1, 50 realistic photographs were used as targets. The correlation between mean estimated height and actual height was .92, and target’s sex and the ratios of head to trunk, which included horizontal ratio (i.e., a ratio of head width to shoulder width) and vertical ratio (i.e., a ratio of head height to stature), were found to be effective on height estimates, although target’s sex was more effective than ratios of head to trunk. In Experiments 2 and 3, the recognizability of target persons was reduced, respectively, by inverting the person photographs and by degrading the various features of the photographs. The main results were that (1) the correlation between mean estimated height and actual height was .88 for the inverted photographs and was .80, on average, for the degraded drawings; (2) target’s sex was consistently influential in both experiments; (3) vertical ratio was effective for the inverted photographs and the mildly degraded drawings but not for the extremely degraded drawings in which only outlines of target persons were depicted; and (4) the estimation for the outlined pictures was likely to be influenced by fit of clothes to targets’ bodies. From these findings, person stimuli were considered to provide a stable metric stick of visual space under naturalistic circumstances.     

Axiomatic summary and deductions from Hering’s principles of visual direction

Hering’s principles of visual direction are summarized axiomatically, and deductions are presented. The deductions allow one to predict when veridical or nonveridical judgments of visual direction should occur and when apparent movement should be seen. These predictions agree with the results obtained in special viewing conditions. However, one of the limitations of the principles is that some of the predictions fail in “normal” viewing conditions.     

Visual behaviors of soccer players while kicking with the inside of the foot

This study analyzed the visual behaviors of soccer players while they kicked with the inside of the foot, which involved near and far aiming skills. Participants (N = 8) were required to step forward and kick a ball to hit a target. The top three scorers were defined as the High-score group, and the three low scorers were defined as the Low-score group. Analysis indicated that the High-score group was characterized by longer quiet eye durations, which were defined as the final fixation durations on the target prior to the initiation of a kicking movement, than the Low-score group in the preparation phase. The High-score group also set their visual pivot on the frontal space between the target and the ball in the kicking phase. These two visual behaviors of the High-score group are important for soccer players to kick a ball successfully with the inside of the foot.