Deterioration of planning ability with age in Japanese monkeys (Macaca fuscata)

To investigate the ability of aged monkeys to plan and the effect of aging on this ability, performance in a food retrieval task was assessed in aged and younger Japanese monkeys (Macaca fuscata). In this task, the monkeys had to retrieve food items by selecting from a set of 9 holes, each of which contained 1 food item. Results showed that task performance declined significantly with age. All monkeys showed, to a greater or lesser extent, some consistent patterns in their sequence of selecting holes for retrieving the food item. An analysis of these selection patterns indicated that the younger monkeys showed more consistent sequences in selection than the aged monkeys. Furthermore, success in the task performance correlated strongly with higher consistency in the sequence of selecting holes. The authors simulated performance for this task by monkeys without any strategies or plans. The results suggest that the empirical data were far more systematic than the simulated data. Thus, the authors conclude that Japanese monkeys have the ability to plan and that this ability to plan deteriorates with age.     

Judgments of grammaticality of Japanese simple sentences involving two arguments in a whole-part relation: a further examination of Chomsky's principle of Full Interpretation

Adult Japanese speakers judged the grammaticality of simple ungramatical sentences involving two arguments, each related with a single verb. The arguments were attached to the same case marker playing the same thematic role in the sentences. Thus the sentences violated Chomsky's principle of Full Interpretation. The two arguments were manipulated such that, on the one hand, one argument (the part-argument) constituted a part of the other argument (the whole-argument) and that, on the other, a part-argument either preceded or followed a whole-argument. Participants rated the sentences using either a conventional 7-point rating scale or magnitude estimation. Findings showed that irrespective of rating method sentences in which the whole-argument preceded the part-argument were judged more grammatical than sentences in which the part-argument preceded the whole-argument. Such an empirical phenomenon is inconsistent with the prediction derived from Chomsky's principle of Full Interpretation, while interestingly it is consistent with the grammar of classical Japanese used about 900 years ago.     

Visual search strategies of baseball batters: eye movements during the preparatory phase of batting

The aim of this study was to analyze visual search strategies of baseball batters during the viewing period of the pitcher's motion. The 18 subjects were 9 experts and 9 novices. While subjects viewed a videotape which, from a right-handed batter's perspective, showed a pitcher throwing a series of 10 types of pitches, their eye movements were measured and analyzed. Novices moved their eyes faster than experts, and the distribution area of viewing points was also wider than that of the experts. The viewing duration of experts of the pitching arm was longer than those of novices during the last two pitching phases. These results indicate that experts set their visual pivot on the pitcher's elbow and used peripheral vision properties to evaluate the pitcher's motion and the ball trajectory.     

Volitional lifestyle in healthy elderly: its relevance to rest-activity cycle,nocturnal sleep,and daytime napping

Sleep-related problems are prevalent among the aged. The present study examined the influence of a mentally active or "volitional" lifestyle on the rest-activity cycle, nocturnal sleep, and daytime napping in the healthy elderly. 14 aged individuals with a high Volitional lifestyle (M = 74.1 yr. old) and 14 with a Low Volitional lifestyle (M = 73.0 yr. old) were screened by questionnaires including the Philadelphia Geriatric Center Morale scale and the Self-confidence scale. Their activity levels were monitored by a wrist actigraph system for 14 consecutive days. They were also asked to record daily sleep logs. The total times of nocturnal sleep and daytime napping did not differ between the groups. However, the acrophases of circadian (tau = 24 hr.) and circasemidian (tau = 12 hr.) activity cycles were more advanced in the Low Volitional group. In addition, the High Volitional group took a daytime nap with a better timing than did the Low Volitional group: the former started a nap during the phase in which their activity level was going down, whereas the latter when their activity level was going up. These results suggest that high volitional lifestyle may be related to better rest-activity cycle in the healthy elderly.     

Perceived standing position after reduction of foot-pressure sensation by cooling the sole

We investigated the influence of the reduction of foot-pressure sensation by cooling the sole of the foot, at 1 degree C for 30 or 40 minutes, on the perception of standing position varied in the anteroposterior direction. The subjects were 16 healthy undergraduates. Firstly, for 4 of the subjects, cooling the sole of the foot decreased sensory information from the mechanoreceptors in the sole, by testing for an increase in the threshold for two-point discrepancy discrimination on the sole of the foot and for the disappearance of postural change with vibration to the sole. Next, the perception of standing position was measured by reproduction of a given standing reference position involving forward or backward leaning under both normal and cooled conditions of the feet. Standing position was varied in relation to the location of the center of foot pressure, defined as distance from the heel in percentage of the length of the foot. The reference positions, representing various locations of the center of foot pressure, were set at 10% increments from 20% to 80% of the length of the foot. With eyes closed, the subject first experienced the reference position and then attempted to reproduce it. The mean location of the center of foot pressure in the quiet standing posture was 45.7%. At the 40%, 50%, and 60% reference positions, those closest to quiet standing, absolute errors of reproduction were significantly larger than at other reference positions in both the normal and the cooled conditions. They were significantly larger in the cooled than in the normal condition. The 50% and 60% reference positions were reproduced significantly further forward in the cooled than in the normal condition. These results may be explained as due to an absence of marked changes in sensory information from both muscular activity and foot pressure when moving to reference positions close to the quiet standing posture.     

Leonardo's constraint: two opaque objects cannot be seen in the same direction

Given Leonardo's constraint that 2 opaque objects cannot be seen in the same direction, how are the regions of objects occluded to 1 eye included in perception? To answer this question, the authors presented 3-dimensional stimuli, similar to the ones that concerned Leonardo, and measured the visual directions of their monocular and binocular regions. When the distance between near and far objects was large, the nonfixated object was seen as double and blurry. Leonardo's constraint was met by seeing the near object as double and transparent or the distant object as double and superimposed. When the distance between near and far objects was small, the constraint was met by a perceptual displacement and compression of parts of the nonfixated object.     

Effect of repetition on grammaticality judgments under objective and subjective self-awareness conditions

Three experiments were performed to investigate the differential effect of repeated presentation of sentences on judgments of grammaticality under the two mental states of objective and subjective self-awareness. In Experiment 1, 22 students judged the relative grammaticality of sentences twice, receiving a repetition treatment between the two judgments. During the repetition phase, they were exposed to a repeated presentation of sentences. The findings showed that repetition makes a judgment criterion more stringent on judgments after repetition than on those before repetition for the subjectively self-aware subjects, while it does not influence the judgments for the objectively self-aware subjects. Experiment 2 was run using a revised procedure with 26 students. The findings showed the expected, interaction, such that the repetition makes a criterion stringent for the subjectively self-aware subjects while it makes the criterion lenient for the objectively self-aware subjects. Experiment 3 examined with 12 students whether the finding for the latter subjects could be explained, by divided attention theory in a concurrent task condition. The findings showed no change of judgment criterion. These findings indicate that repeated exposure to the sentences exerts differential effects on grammaticality judgments dependent on whether the subjects are objectively or subjectively self-aware.     

Is Trait Rumination Associated with the Ability to Generate Effective Problem Solving Strategies? Utilizing Two Versions of the Means-Ends Problem-Solving Test

This study examined the relationship between trait rumination and the effectiveness of problem solving strategies as assessed by the Means-Ends Problem-Solving Test (MEPS) in a nonclinical population. The present study extended previous studies in terms of using two instructions in the MEPS: the second-person, actual strategy instructions, which has been utilized in previous studies on rumination, and the third-person, ideal-strategy instructions, which is considered more suitable for assessing the effectiveness of problem solving strategies. We also replicated the association between rumination and each dimension of the Social Problem-Solving Inventory-Revised Short Version (SPSI-R:S). Japanese undergraduate students (N = 223) completed the Beck Depression Inventory-Second Edition, Ruminative Responses Scale (RRS), MEPS, and SPSI-R:S. One half of the sample completed the MEPS with the second-person, actual strategy instructions. The other participants completed the MEPS with the third-person, ideal-strategy instructions. The results showed that neither total RRS score, nor its subscale scores were significantly correlated with MEPS scores under either of the two instructions. These findings taken together with previous findings indicate that in nonclinical populations, trait rumination is not related to the effectiveness of problem solving strategies, but that state rumination while responding to the MEPS deteriorates the quality of strategies. The correlations between RRS and SPSI-R:S scores indicated that trait rumination in general, and its brooding subcomponent in particular are parts of cognitive and behavioral responses that attempt to avoid negative environmental and negative private events. Results also showed that reflection is a part of active problem solving.