Hearing what the body feels: auditory encoding of rhythmic movement

Phillips-Silver and Trainor (Phillips-Silver, J., Trainor, L.J., (2005). Feeling the beat: movement influences infants' rhythm perception. Science, 308, 1430) demonstrated an early cross-modal interaction between body movement and auditory encoding of musical rhythm in infants. Here we show that the way adults move their bodies to music influences their auditory perception of the rhythm structure. We trained adults, while listening to an ambiguous rhythm with no accented beats, to bounce by bending their knees to interpret the rhythm either as a march or as a waltz. At test, adults identified as similar an auditory version of the rhythm pattern with accented strong beats that matched their previous bouncing experience in comparison with a version whose accents did not match. In subsequent experiments we showed that this effect does not depend on visual information, but that movement of the body is critical. Parallel results from adults and infants suggest that the movement-sound interaction develops early and is fundamental to music processing throughout life.     

One, two, three, four, nothing more: an investigation of the conceptual sources of the verbal counting principles

Since the publication of [Gelman, R., & Gallistel, C. R. (1978). The child's understanding of number. Cambridge, MA: Harvard University Press.] seminal work on the development of verbal counting as a representation of number, the nature of the ontogenetic sources of the verbal counting principles has been intensely debated. The present experiments explore proposals according to which the verbal counting principles are acquired by mapping numerals in the count list onto systems of numerical representation for which there is evidence in infancy, namely, analog magnitudes, parallel individuation, and set-based quantification. By asking 3- and 4-year-olds to estimate the number of elements in sets without counting, we investigate whether the numerals that are assigned cardinal meaning as part of the acquisition process display the signatures of what we call "enriched parallel individuation" (which combines properties of parallel individuation and of set-based quantification) or analog magnitudes. Two experiments demonstrate that while "one" to "four" are mapped onto core representations of small sets prior to the acquisition of the counting principles, numerals beyond "four" are only mapped onto analog magnitudes about six months after the acquisition of the counting principles. Moreover, we show that children's numerical estimates of sets from 1 to 4 elements fail to show the signature of numeral use based on analog magnitudes - namely, scalar variability. We conclude that, while representations of small sets provided by parallel individuation, enriched by the resources of set-based quantification are recruited in the acquisition process to provide the first numerical meanings for "one" to "four", analog magnitudes play no role in this process.     

Personality and cognitive processes in life and death decision making: An exploration into the source of judgment errors by police special squads

This study sought to understand judgment errors by special police units such as those documented after the assault by the Bureau of Alcohol, Tobacco and Firearms on the Branch Davidians near Waco, Texas. The study examined the relation between personality traits, the cognitive organization of safety and survival skills, and past deadly force encounters in 131 tactical and command officers of Violent Crimes and Fugitives Task Forces, and as they executed live high‐risk arrest warrants in an all‐inclusive decision‐making simulation environment. Logistic regressions showed that getting shot on the job was related to very low neuroticism and low sensation (experience) seeking among officers. Getting shot in a deadly force encounter during a simulated team entry was also related to low neuroticism and low experience seeking. Making safety and survival errors in a simulated entry was positively related to toughmindedness in Task Force tactical officers but negatively related to toughmindedness in Task Force leaders. Principle components factor analysis of 27 self‐reported safety and survival competencies showed that, generally, TF leaders reasoned with higher cognitive processes of analysis and deliberation while tactical personnel reasoned more in terms of reactive and procedural knowledge. Getting shot during a simulated dangerous encounter was more likely to occur when there was a mismatch between task demands and an officer's preference of one knowledge system over another. It was speculated that the poor judgment by command staff at Waco might have been related to their use of a procedural knowledge system when higher cognitive processes were needed. Greater experience with executing arrest warrants would have triggered the recognition of a serious anomaly, which would have primed the use of higher cognitive processes.     

Different action patterns for cooperative and competitive behaviour

The aim of the present study is to elucidate the influence of context on the kinematics of the reach-to-grasp movement. In particular, we consider two basic modes of social cognition, namely cooperation and competition. In two experiments kinematics of the very same action - reaching-to-grasp a wooden block - were analyzed in two different contexts provided by a cooperative task and competitive task. For the 'cooperation' tasks two participants were required to reach and grasp their respective objects and to cooperate to join the two objects in specific configurations in the middle of the working surface. For the 'competition' tasks, the two participants had to compete to place their own object first in the middle of the working surface. Results revealed specific kinematic patterns for cooperation and competition which were distinct from similar actions performed by each participant in isolation. Further, during the cooperation tasks, a high level of correlation between key kinematical parameters of the two participants was found. In accordance with evidence from neuroimaging, developmental and social psychology our results suggest the existence of motor patterns which reflect the intention to act in a social context.     

Suitable stimuli to obtain (no) gender differences in the speed of cognitive processes involved in mental rotation

Gender differences in speed of perceptual comparison, of picture-plane mental rotation, and in switching costs between trials that do and do not require mental rotation, were investigated as a function of stimulus material with a total sample size of N=360. Alphanumeric characters, PMA symbols, animal drawings, polygons and 3D cube figures were used with an otherwise completely equivalent experimental design in which age and speed-based IQ were comparable across male and female groups. Small gender-related differences in speed of perceptual comparison were found with the magnitude as well as the direction depending upon the stimulus material. Polygons were the only material that produced substantial and reliable gender differences in mental rotation speed, and additionally revealed gender differences in switching costs. Thus, whereas gender differences in paper-pencil mental rotation tests constitute an empirical reality, the generalization that men outperform women in the speed of mental rotation was not supported in the present experiment.     

Switching between sensory and affective systems incurs processing costs

Recent models of the conceptual system hold that concepts are grounded in simulations of actual experiences with instances of those concepts in sensory-motor systems (e.g., Barsalou, 1999, 2003; Solomon & Barsalou, 2001). Studies supportive of such a viewhave shown that verifying a property of a concept in one modality, and then switching to verify a property of a different concept in a different modality generates temporal processing costs similar to the cost of switching modalities in perception. In addition to non-emotional concepts, the present experiment investigated switching costs in verifying properties of positive and negative (emotional) concepts. Properties of emotional concepts were taken from vision, audition, and the affective system. Parallel to switching costs in neutral concepts, the study showed that for positive and negative concepts, verifying properties from different modalities produced processing costs such that reaction times were longer and error rates were higher. Importantly, this effect was observed when switching from the affective system to sensory modalities, and vice-versa. These results support the embodied cognition view of emotion in humans.     

What is adaptive about adaptive decision making? A parallel constraint satisfaction account

There is broad consensus that human cognition is adaptive. However, the vital question of how exactly this adaptivity is achieved has remained largely open. Herein, we contrast two frameworks which account for adaptive decision making, namely broad and general single-mechanism accounts vs. multi-strategy accounts. We propose and fully specify a single-mechanism model for decision making based on parallel constraint satisfaction processes (PCS-DM) and contrast it theoretically and empirically against a multi-strategy account. To achieve sufficiently sensitive tests, we rely on a multiple-measure methodology including choice, reaction time, and confidence data as well as eye-tracking. Results show that manipulating the environmental structure produces clear adaptive shifts in choice patterns – as both frameworks would predict. However, results on the process level (reaction time, confidence), in information acquisition (eye-tracking), and from cross-predicting choice consistently corroborate single-mechanisms accounts in general, and the proposed parallel constraint satisfaction model for decision making in particular.     

Working Wonders? Investigating insight with magic tricks

We propose a new approach to differentiate between insight and noninsight problem solving, by introducing magic tricks as problem solving domain. We argue that magic tricks are ideally suited to investigate representational change, the key mechanism that yields sudden insight into the solution of a problem, because in order to gain insight into the magicians’ secret method, observers must overcome implicit constraints and thus change their problem representation. In Experiment 1, 50 participants were exposed to 34 different magic tricks, asking them to find out how the trick was accomplished. Upon solving a trick, participants indicated if they had reached the solution either with or without insight. Insight was reported in 41.1% of solutions. The new task domain revealed differences in solution accuracy, time course and solution confidence with insight solutions being more likely to be true, reached earlier, and obtaining higher confidence ratings. In Experiment 2, we explored which role self-imposed constraints actually play in magic tricks. 62 participants were presented with 12 magic tricks. One group received verbal cues, providing solution relevant information without giving the solution away. The control group received no informative cue. Experiment 2 showed that participants’ constraints were suggestible to verbal cues, resulting in higher solution rates. Thus, magic tricks provide more detailed information about the differences between insightful and noninsightful problem solving, and the underlying mechanisms that are necessary to have an insight.     

Simulating sensorimotor metaphors: Novel metaphors influence sensory judgments

Embodied cognition theory proposes that individuals’ abstract concepts can be associated with sensorimotor processes. The authors examined the effects of teaching participants novel embodied metaphors, not based in prior physical experience, and found evidence suggesting that they lead to embodied simulation, suggesting refinements to current models of embodied cognition. Creating novel embodiments of abstract concepts in the laboratory may be a useful method for examining mechanisms of embodied cognition.     

Visual experience influences the interactions between fingers and numbers

Though a clear interaction between finger and number representations has been demonstrated, what drives the development of this intertwining remains unclear. Here we tested early blind, late blind and sighted control participants in two counting tasks, each performed under three different conditions: a resting condition, a condition requiring hands movements and a condition requiring feet movements. In the resting condition, every sighted and late blind spontaneously used their fingers, while the majority of early blind did not. Sighted controls and late blind were moreover selectively disrupted by the interfering hand condition, while the early blind who did not use the finger-counting strategy remained unaffected by the interference conditions. These results therefore demonstrate that visual experience plays an important role in implementing the sensori-motor habits that drive the development of finger–number interactions.