Geoffrey Bingham

Long-distance throwing is uniquely human and enabled Homo sapiens to survive and even thrive during the ice ages. The precise motoric timing required relates throwing and speech abilities as dependent on the same uniquely human brain structures. Evidence from studies of brain evolution is consistent with this understanding of the evolution and success of H. sapiens. Recent theories of language development find readiness to develop language capabilities in perceptual biases that help generate ability to detect relevant higher order acoustic units that underlie speech. Might human throwing capabilities exhibit similar forms of readiness? Recently, human perception of optimal objects for long-distance throwing was found to exhibit a size–weight relation similar to the size–weight illusion; greater weights were picked for larger objects and were thrown the farthest. The size–weight illusion is: lift two objects of …

The authors used a virtual environment to investigate visual control of reaching and monocular and binocular perception of egocentric distance, size, and shape. With binocular vision, the results suggested use of disparity matching. This was tested and confirmed in the virtual environment by eliminating other information about contact of hand and target. Elimination of occlusion of hand by target destabilized monocular but not binocular performance. Because the virtual environment entails accommodation of an image beyond reach, the authors predicted overestimation of egocentric distances in the virtual relative to actual environment. This was confirmed. The authors used-2 diopter glasses to reduce the focal distance in the virtual environment. Overestimates were reduced by half. The authors conclude that calibration of perception is required for accurate feedforward reaching and that disparity matching is optimal …

In this investigation of monocular perception of egocentric distance, the authors advocate the necessity of a perception–action approach because calibration is intrinsic to definite distance perception. A helmet-mounted camera and display were used to isolate optic flow generated by participants' head movements toward a target, and participants' reaches to place a stylus either in a target hole (Experiments 1, 2, and 4) or aligned under a target surface (Experiment 3) were analyzed. Conclusions are that binocular distance perception is accurate, monocular distance perception yields compression that is not eliminated by feedback, but feedback is used to eliminate underestimation generated by restriction of the size of the visual field.(PsycINFO Database Record (c) 2016 APA, all rights reserved)

The authors investigated event dynamics as a determinant of the perceptual significance of forms of motion. Patch-light displays were recorded for 9 simple events selected to represent rigid-body dynamics, biodynamics, hydrodynamics, and aerodynamics. Observers described events in a free-response task or by circling properties in a list. Cluster analyses performed on descriptor frequencies reflected the dynamics. Observers discriminated hydro-vs aerodynamic events and animate vs inanimate events. The latter result was confirmed by using a forced-choice task. Dynamical models of the events led us to consider energy flows as a determinant of kinematic properties that allowed animacy to be distinguished. Orientation was manipulated in 3 viewing conditions. Descriptions varied with absolute display orientation rather than the relative orientation of display and observer.(PsycINFO Database Record (c) 2016 …

An approach to the problem of organization in human action is presented. The approach describes the observable forms of behavior in terms of the dynamics of task-specific devices (TSD). The properties of a TSD delineate problems for research. The properties are task specificity, smartness, determinism, soft assembly and reduction, controllability, scale specificity, assembly over properties of organism and environment, and modifiability to new purpose. Nonlinear properties of four subsystems of the human action system are described. The subsystems are the link-segment system, the musculotendon system, the circulatory system, and the nervous system. A methodological dilemma is created by the need to do justice in description to all four subsystems while at the same time not being completely overwhelmed by the extreme complexity. A strategic resolution is to describe the simpler dynamics of TSD's. This …

Observers are able to judge accurately the weight lifted by another person when only the motions of reflective patches attached to the lifter's major limb joints and head can be seen (Runeson & Frykholm, 1981). What properties of these complex kinematic patterns allow judgments of weight to be made? The pattern of variation in velocity of the lifted object over position is explored as a source of information for weight: It is found to provide limited information. How are variations in kinematic patterns scaled to allow judgments of weight, a kinetic quantity? The possibility of a source of information for scaling in the kinematics is investigated. Judgments based only on patch-light displays are accurate to a degree that is improved by an extrinsic scaling basis. Finally, the sensitivity to scaling of alternative metrics used in judging is explored. Intrinsic metrics are discovered to be less sensitive to the absence of an extrinsic …

Bingham, Schmidt, & Rosenblum,(1989) showed that people are able to select, by hefting balls, the optimal weight for each size ball to be thrown farthest. We now investigate function learning and smart mechanisms as hypotheses about how this affordance is perceived. Twenty-four unskilled adult throwers learned to throw by practicing with a subset of balls that would only allow acquisition of the ability to perceive the affordance if hefting acts as a smart mechanism to provide access to a single information variable that specifies the affordance. Participants hefted 48 balls of different sizes and weights and judged throwability. Then, participants, assigned to one of four groups, practiced throwing (three groups with vision and one without) for a month using different subsets of balls. Finally, hefting and throwing were tested again with all the balls. The results showed:(1) inability to detect throwability before practice,(2 …

Feedback is a central feature of neural systems and of crucial importance to human behaviour as shown in goal directed actions such as reaching-to-grasp. One important source of feedback in reach-to-grasp behaviour arises from the haptic information obtained after grasping an object. We manipulated the felt distance and/or size of a visually constant object to explore the role of haptic information in the calibration of reaching and grasping. Crucially, our design explored post-adaptation effects rather than the previously documented role of haptic information in movement organisation. A post-adaptation reach-to-grasp task showed: (1) distorted haptic feedback caused recalibration; (2) reach distance and grasp size could be calibrated separately but, if calibrated simultaneously, then (3) recalibration was greater when distance and size changed in a consistent (e.g. reaching for a larger object at a greater …

Extensive research has identified the affordances used to guide actions, as originally conceived by Gibson (Perceiving, acting, and knowing: towards an ecological psychology. Erlbaum, Hillsdale, 1977; The ecological approach to visual perception. Erlbaum, Hillsdale, 1979/1986). We sought to discover the object affordance properties that determine the spatial structure of reach-to-grasp movements—movements that entail both collision avoidance and targeting. First, we constructed objects that presented a significant collision hazard and varied properties relevant to targeting, namely, object width and size of contact surface. Participants reached-to-grasp objects at three speeds (slow, normal, and fast). In Experiment 1, we explored a “stop” task where participants grasped the objects without moving them. In Experiment 2, we studied “fly-through” movements where the objects were lifted. We discovered the …

Developmental coordination disorder affects a relatively large proportion (5%-6%) of the childhood population. Severity of the disorder varies but there is a great need for therapeutic intervention. We propose a method for the training of manual actions in children with developmental coordination disorder. Our solution is achieved by applying haptic virtual reality technology to attack the difficulties that children with developmental coordination disorder evidence. Our results show that children with developmental coordination disorder are able to learn complex motor skills if proper training methods are employed. These findings conflict with reports of impaired motor learning in developmental coordination disorder because of underactivation of cerebellar and parietal networks.