The purpose of the current experiments was to examine whether the problems associated with grasp posture planning during bimanually incongruent movements are due to crosstalk at the motor programming level. Participants performed a grasping and placing task in which they grasped two objects from a table and placed them onto a board to targets that required identical (congruent) or non-identical...

DM-GRASP is an immunoglobulin superfamily cell adhesion molecule that is expressed in both the developing nervous and immune system. Specific populations of neurons respond to DM-GRASP substrates appears to require homophilic interactions between DM-GRASP molecules. We were interested in determining whether DM-GRASP interacts heterophilically with other ligands as well. We have found that eleve...

When a multi-fingered hand grasps an object, the ways to grasp it stably are infinite, and thus an optimal grasp planning is necessary to find the relatively optimized grasp points on object for achieving the objective of the given grasping and manipulating task. For this, we first define several grasp indices to evaluate the quality of each feasible grasp. Since the physical meanings of the de...

We investigate the degree to which participants’ predictions of a simulated stock price are influenced by predictions made by a herd of five other (fictitious) participants when they consist of a majority or minority. The results of Experiment 1 showed that the participants followed a majority herd independently of whether its predictions were accurate or random. In Experiment 2, the majority i...

The cerebellar cortex and nuclei play important roles in the learning, planning, and execution of reach-to-grasp and prehensile movements. However, few studies have investigated the signals carried by cerebellar neurons during reach-to-grasp, particularly signals relating to target object properties, hand shape, and grasp force. In this study, the simple spike discharge of 77 Purkinje cells was...

This study was designed to investigate the developmental progression in pencil and crayon grip. The subjects were 320 nondysfunctional children aged 3.0 to 6.11 years, with 20 boys and 20 girls at each 6-month age interval. On the basis of a review of the literature, developmental pencil and crayon grips were defined for the study, and the type of grips each child used to perform a drawing task...

Recent evidence suggests adults and infants selectively attend to features of action, such as how a hand contacts an object. The current research investigated whether this bias stems from infants' processing of the functional consequences of grasps: understanding that different grasps afford different future actions. A habituation paradigm assessed 10-month-old infants' (N = 62) understanding o...

Many of us will be familiar with the parable of the blind men and the elephant, beautifully retold by the 19th century American poet John Godfrey Saxe. In this tale, each man in turn describes the small part of the elephant they are touching (the flank, the tusk, the trunk, etc.), declaring with confidence that they know the true nature of the object (‘It’s a wall!’, ‘A spear!’, ‘A snake!’). Sa...

THE following study is concerned with the codification of reality, and more particularly, with the nonlineal apprehension of reality among the people of the Trobriand Islands, in contrast to our own lineal phrasing. Basic to my investigation is the assumption that a member of a given society not only codifies experienced reality through the use of the specific language and other patterned behav...

There are two problems of behavior which any theory of motivation must come to grips with. They may finally reduce to one; but it will simplify the exposition which follows to maintain the distinction in this paper. The first problem is to account for an individual's selection of one path of action among a set of possible alternatives. The second problem is to account for the amplitude or vigor...