The role of directional compatibility was investigated during the production of in-phase and anti-phase coordination patterns involving both arms as well as the head. Our first aim was to compare the quality of coordination between both arms when symmetrical arm posture manipulations were used to disentangle muscle homology from the mutual direction of limb motions in extrinsic space. Findings ...

In this paper, we introduce our life-size talking head robotic system, “Mask-bot”, developed as a platform to support and accelerate human-robot communication research. The “Mask-bot” hardware consists of a semi-transparent plain mask, a portable LED projector with a fish-eye conversion lens mounted behind the mask, a pan-tilt unit and a mounting base. The hardware is driven by a software anima...

In this paper, we demonstrate how a new interactive 3D desktop metaphor based on two-handed 3D direct manipulation registered with head-tracked stereo viewing can be applied to the task of constructing animated characters. In our configuration, a six degree-of-freedom head-tracker and CrystalEyes shutter glasses are used to produce stereo images that dynamically follow the user head motion. 3D ...

In humans, whose ears are fixed on the head, auditory stimuli are initially registered in space relative to the head. Eventually, locations of sound sources need to be encoded also relative to the body, or in absolute allocentric space, to allow orientation toward the sounds sources and consequent action. We can therefore distinguish between two spatial representation systems: a basic head-cent...

Registration of ego-motion is important to accurately navigate through space. Movements of the head and eye relative to space are registered through the vestibular system and optical flow, respectively. Here, we address three questions concerning the visual registration of self-rotation. (1) Eye-in-head movements provide a link between the motion signals received by sensors in the moving eye an...

The vestibular sensory apparatus and associated vestibular nuclei are generally thought to encode angular head velocity during our daily activities. However, in addition to direct inputs from vestibular afferents, the vestibular nuclei receive substantial projections from cortical, cerebellar, and other brainstem structures. Given this diversity of inputs, the question arises: How are the respo...

A major goal of this study was to characterize the cervicocollic reflexes (CCRs) in awake squirrel monkeys and compare it to observations in cat. This was carried out by stabilizing the head in space while rotating the lower body. The magnitude and phase of the torque produced between the head and the restraint system was used as an indicator of the CCR. Many properties of the squirrel monkey's...

The supplementary eye fields (SEFs), located on the dorsomedial surface of the frontal cortex, are involved in high-level aspects of saccade generation. Some reports suggest that the same area could also be involved in the generation of motor commands for the head. If so, it is important to establish whether this structure encodes eye and head commands separately or gaze commands that give rise...

INTRODUCTION Obstructive Sleep Apnea (OSA) is characterized by repeated episodes of upper airway obstruction during sleep. OBJECTIVE The objective of this study is to verify the craniofacial characteristics and craniocervical posture of OSA and healthy subjects, determining possible relationships with the apnea/hypopnea index (AHI). METHODS This case-control study evaluated 21 subjects with...