Enhancement of Speech-Relevant Auditory Acuity in Absolute Pitch Possessors

Absolute pitch (AP) is the ability to identify the frequency or musical name of a specific tone, or to identify a tone without comparing it with any objective reference tone. While AP has recently been shown to be associated with morphological changes and neurophysiological adaptations in the planum temporale, a cortical area in the brain involved in speech perception processes, no behavioral evidence of speech-relevant auditory acuity in any AP possessors has hitherto been reported. In order to seek such evidence, in the present study, 15 professional musicians with AP and 14 without AP, all of whom had acquired Japanese as their first language, were asked to identify isolated Japanese syllables as quickly as possible after these syllables were presented auditorily. When the mean latency to the syllable identification was compared, it was significantly shorter in AP possessors than in non-AP possessors whether the presented syllables were those used as Japanese labels representing the 7 tones constituting an octave or not. The latency to hear the stimuli per se did not differ according to whether the participants were AP possessors or not. The results indicate the possibility that possessing AP provides one with extraordinarily enhanced acuity to individual syllables per se as fundamental units of a segmented word in the speech stream

The efficacy of musical emotions provoked by Mozart's music for the reconciliation of cognitive dissonance.

Debates on the origin and function of music have a long history. While some scientists argue that music itself plays no adaptive role in human evolution, others suggest that music clearly has an evolutionary role, and point to music's universality. A recent hypothesis suggested that a fundamental function of music has been to help mitigating cognitive dissonance, which is a discomfort caused by holding conflicting cognitions simultaneously. It usually leads to devaluation of conflicting knowledge. Here we provide experimental confirmation of this hypothesis using a classical paradigm known to create cognitive dissonance. Results of our experiment reveal that the exposure to Mozart's music exerted a strongly positive influence upon the performance of young children and served as basis by which they were enabled to reconcile the cognitive dissonance

Music can reduce cognitive dissonance

The fundamental cognitive functions of music in the brain have not been known and evolutionary reasons for musical abilities seem mysterious. A recent hypothesis suggested that a fundamental function of music has been to help mitigating cognitive dissonances. A cognitive dissonance is "a discomfort caused by holding conflicting cognitions" simultaneously; it usually leads to devaluation of conflicting knowledge. Since every concept implies some degree of contradictions to other knowledge, unmitigated cognitive dissonances could prevent evolution of cognition. Thus music might be fundamental for the evolution of cognition. Here we provide experimental confirmation of this hypothesis using a classical paradigm known to induce a cognitive dissonance and devaluation of a dissonant object; in presence of music devaluation has not occurred

Free-Ranging Macaque Mothers Exaggerate Tool-Using Behavior when Observed by Offspring

The population-level use of tools has been reported in various animals. Nonetheless, how tool use might spread throughout a population is still an open question. In order to answer that, we observed the behavior of inserting human hair or human-hair-like material between their teeth as if they were using dental floss in a group of long-tailed macaques (Macaca fascicularis) in Thailand. The observation was undertaken by video-recording the tool-use of 7 adult females who were rearing 1-year-old infants, using the focal-animal-sampling method. When the data recorded were analyzed separately according to the presence/absence of the infant of the target animal in the target animal's proximity, the pattern of the tool-using action of long-tailed adult female macaques under our observation changed in the presence of the infant as compared with that in the absence of the infant so that the stream of tool-using action was punctuated by more pauses, repeated more often, and performed for a longer period during each bout in the presence of the infant. We interpret this as evidence for the possibility that they exaggerate their action in tool-using so as to facilitate the learning of the action by their own infants

Goal attribution to inanimate moving objects by Japanese macaques (Macaca fuscata)

Humans interpret others’ goals based on motion information, and this capacity contributes to our mental reasoning. The present study sought to determine whether Japanese macaques (Macaca fuscata) perceive goal-directedness in chasing events depicted by two geometric particles. In Experiment 1, two monkeys and adult humans were trained to discriminate between Chasing and Random sequences. We then introduced probe stimuli with various levels of correlation between the particle trajectories to examine whether participants performed the task using higher correlation. Participants chose stimuli with the highest correlations by chance, suggesting that correlations were not the discriminative cue. Experiment 2 examined whether participants focused on particle proximity. Participants differentiated between Chasing and Control sequences; the distance between two particles was identical in both. Results indicated that, like humans, the Japanese macaques did not use physical cues alone to perform the discrimination task and integrated the cues spontaneously. This suggests that goal attribution resulting from motion information is a widespread cognitive phenotype in primate species

Grooming-at-a-distance by exchanging calls in non-human primates

International audienceThe 'social bonding hypothesis' predicts that, in large social groups, functions of gestural grooming should be partially transferred to vocal interactions. Hence, vocal exchanges would have evolved in primates to play the role of grooming-at-a-distance in order to facilitate the maintenance of social cohesion. However, there are few empirical studies testing this hypothesis. To address this point, we compared the rate of contact call exchanges between females in two captive groups of Japanese macaques as a function of female age, dominance rank, genetic relatedness and social affinity measured by spatial proximity and grooming interactions. We found a significant positive relationship between the time spent on grooming by two females and the frequency with which they exchanged calls. Our results conform to the predictions of the social bonding hypothesis, i.e. vocal exchanges can be interpreted as grooming-at-a-distanc

Copying hierarchical leaders' voices? Acoustic plasticity in female Japanese macaques

It has been historically claimed that call production in nonhuman primates has been shaped by genetic factors, although, recently socially-guided plasticity and cortical control during vocal exchanges have been observed. In humans, context-dependent vocal convergence with relatives, friends or leaders' voices can be found. Comparative studies with monkeys and apes presenting tolerant social organizations have demonstrated that affiliative bonding is the determining factor of convergence. We tested whether vocal copying could also exist in a primate species with a despotic social organization. We compared the degree of inter-individual similarity of contact calls in two groups of Japanese macaques as a function of age, dominance rank, maternal kin and affiliative bonds. We found a positive relationship between dyadic acoustic similarity and female rank differences. Since most call exchanges were initiated by dominant females and since this species is known for the ability of responders to acoustically match initiators" calls, we conclude that high social status may motivate vocal convergence in this despotic society. Accordingly, intra-individual comparisons showed that isolated calls were more stereotyped than exchanged calls, and that dominants had more stereotyped voices than subordinates. This opens new lines of research with regard to social motivation guiding acoustic plasticity in primates

Evaluation of Single-Bundle versus Double-Bundle PCL Reconstructions with More Than 10-Year Follow-Up

Background. Posterior cruciate ligament (PCL) injuries are not rare in acute knee injuries, and several recent anatomical studies of the PCL and reconstructive surgical techniques have generated improved patient results. Now, we have evaluated PCL reconstructions performed by either the single-bundle or double-bundle technique in a patient group followed up retrospectively for more than 10 years. Methods. PCL reconstructions were conducted using the single-bundle (27 cases) or double-bundle (13 cases) method from 1999 to 2002. The mean age at surgery was 34 years in the single-bundle group and 32 years in the double-bundle group. The mean follow-up period was 12.5 years. Patients were evaluated by Lysholm scoring, the gravity sag view, and knee arthrometry. Results. The Lysholm score after surgery was 89.1±5.6 points for the single-bundle group and 91.9±4.5 points for the double-bundle group. There was no significant difference between the methods in the side-to-side differences by gravity sag view or knee arthrometer evaluation, although several cases in both groups showed a side-to-side difference exceeding 5 mm by the latter evaluation method. Conclusions. We found no significant difference between single- and double-bundle PCL reconstructions during more than 10 years of follow-up

A Low-Tech Bioreactor System for the Enrichment and Production of Ureolytic Microbes

Ureolysis-driven microbially induced carbonate precipitation (MICP) has recently received attention for its potential biotechnological applications. However, information on the enrichment and production of ureolytic microbes by using bioreactor systems is limited. Here, we report a low-tech down-flow hanging sponge (DHS) bioreactor system for the enrichment and production of ureolytic microbes. Using this bioreactor system and a yeast extract-based medium containing 0.17 M urea, ureolytic microbes with high potential urease activity (> 10 μmol urea hydrolyzed per min per ml of enrichment culture) were repeatedly enriched under non-sterile conditions. In addition, the ureolytic enrichment obtained in this study showed in vitro calcium carbonate precipitation. Fluorescence in situ hybridization analysis showed the existence of bacteria of the phylum Firmicutes in the bioreactor system. Our data demonstrate that this DHS bioreactor system is a useful system for the enrichment and production of ureolytic microbes for MICP applications