From dichoptic to dichotic: historical contrasts between binocular vision and binaural hearing

Phenomena involving vision with two eyes have been commented upon for several thousand years whereas those concerned with hearing with two ears have a much more recent history. Studies of binocular vision and binaural hearing are contrasted with respect to the singleness of the percept, experimental manipulations of dichoptic and dichotic stimuli, eye and ear dominance, spatial localisation, and the instruments used to stimulate the paired organs. One of the principal phenomena that led to studies of dichotic hearing was dichoptic colour mixing. There was similar disagreement regarding whether colours or sounds could be combined when presented to different paired organs. Direction and distance in visual localisation were analysed before those for auditory localisation, partly due to difficulties in controlling the stimuli. Instruments for investigating binocular vision, like the stereoscope and pseudoscope, were invented before those for binaural hearing, like the stethophone and pseudophone.     

Lessons from longitudinal studies for new approaches to the DSM-V: the FFM and FFT

After brief comments about each target article, we discuss their significance for the DSM-V, the implications for personality disorders of universal trait developmental trends, and our emerging theoretical model, the Five-Factor Theory, which provides an integrative context for these remarkable findings.     

Optimum take-off angle in the standing long jump

The aim of this study was to identify and explain the optimum projection angle that maximises the distance achieved in a standing long jump. Five physically active males performed maximum-effort jumps over a wide range of take-off angles, and the jumps were recorded and analysed using a 2-D video analysis procedure. The total jump distance achieved was considered as the sum of three component distances (take-off, flight, and landing), and the dependence of each component distance on the take-off angle was systematically investigated. The flight distance was strongly affected by a decrease in the jumper's take-off speed with increasing take-off angle, and the take-off distance and landing distance steadily decreased with increasing take-off angle due to changes in the jumper's body configuration. The optimum take-off angle for the jumper was the angle at which the three component distances combined to produce the greatest jump distance. Although the calculated optimum take-off angles (19-27 degrees) were lower than the jumpers' preferred take-off angles (31-39 degrees), the loss in jump distance through using a sub-optimum take-off angle was relatively small.     

Familiarization to treadmill running in young unimpaired adults

This study investigated the time needed for familiarization to treadmill running. Seventeen young healthy adults, who were inexperienced on a treadmill, ran for 11 min on a treadmill at their self-selected speed. Discrete sagittal-plane angular kinematic parameters of the pelvis, hip, knee and ankle, and cadence and stride time data were captured with a three-dimensional motion analysis system at 0, 2, 4, 6, 8 and 10 min. Participants were considered familiarized to treadmill running by 6 min, as there were no significant changes in any dependent variables from this time. Furthermore, mean absolute difference scores between consecutive times were minimal (1.3 degrees ) and the average intraclass correlation coefficient [ICC(2,1)=.95] was maximal and highly reliable by this time. Future studies comparing treadmill and overground running need to provide an adequate treadmill familiarization time of at least 6 min prior to data capture of sagittal-plane kinematic events.     

Warnings reduce the magnitude of the imagination inflation effect

Imagination inflation occurs when people increase their confidence that an event actually happened after imagining the details of the event. The purpose of this study was to determine whether warning people about the imagination inflation effect would reduce their tendency to inflate their ratings of the imagined events. In one condition, we warned participants about the deleterious effects of imagining distant events. Compared with a control group that did not receive a warning, this group produced a significantly smaller imagination inflation effect. We discuss these results and the imagination inflation effect in the context of 2 theories designed to explain the cognitive processes that produce this effect.     

The Chimenti controversy

Jacopo Chimenti (c 1551-1640), an artist from Empoli, made two sketches of a young man holding a compass and a plumb line. When these were seen, mounted next to one another, by Alexander Crum Brown in 1859, he combined them by overconvergence and described the stereoscopic depth he saw. Brown's informal observation was conveyed to David Brewster, who suggested that the drawings were produced for a stereoscope, possibly made by Giovanni Battista della Porta. There followed a bitter debate about the supposed stereoscopic effects that could be seen when the pictures combined. Brewster's claims were finally dispelled when precise measurements were made of the drawings: some parts were stereoscopic and others were pseudoscopic. Brewster's attempts to wrest the invention of the stereoscope from Wheatstone were unsuccessful.     

Classification of domestic cat (Felis catus) vocalizations by naive and experienced human listeners

To test for possible functional referentiality in a common domestic cat (Felis catus) vocalization, the authors conducted 2 experiments to examine whether human participants could classify meow sounds recorded from 12 different cats in 5 behavioral contexts. In Experiment 1, participants heard singlecalls, whereas in Experiment 2, bouts of calls were presented. In both cases, classification accuracy was significantly above chance, but modestly so. Accuracy for bouts exceeded that for single calls. Overall, participants performed better in classifying individual calls if they had lived with, interacted with, and had a general affinity for cats. These results provide little evidence of referentiality suggesting instead that meows are nonspecific, somewhat negatively toned stimuli that attract attention from humans. With experience, human listeners can become more proficient at inferring positive-affect states from cat meows.