Linking Signal Relevancy and Intensity in Predictive Tactile Suppression.

Predictable somatosensory feedback leads to a reduction in tactile sensitivity. This phenomenon, called , relies on a mechanism that uses an efference copy of motor commands to help select relevant aspects of incoming sensory signals. We investigated whether tactile suppression is modulated by (a) the task-relevancy of the predicted consequences of movement and (b) the intensity of related somatosensory feedback signals.

Virtual Hand Illusion in younger and older adults.

Introduction: Embodiment involves experiencing ownership over our body and localizing it in space and is informed by multiple senses (visual, proprioceptive and tactile). Evidence suggests that embodiment and multisensory integration may change with older age. The Virtual Hand Illusion (VHI) has been used to investigate multisensory contributions to embodiment, but has never been evaluated in older adults.

The Weighting of Cues to Upright Following Stroke With and Without a History of Pushing.

Objective: Perceived upright depends on three main factors: vision, graviception, and the internal representation of the long axis of the body. We assessed the relative contributions of these factors in individuals with sub-acute and chronic stroke and controls using a novel tool; the Oriented Character Recognition Test (OCHART). We also considered whether individuals who displayed active pushing or had a history of pushing behaviours had different weightings than those with no signs of pushing.

Predicted reach consequences drive time course of tactile suppression.

Sensitivity to touch is reduced during movement; this tactile suppression is likely the result of a mechanism that suppresses self-generated movement consequences. We sought to determine whether tactile suppression is modulated by naturally evoked changes in movement speed driven by task precision demands (Exp.1), and by changes in predicted movement consequences (Exp.

The effect of hand position on perceived finger orientation in left- and right-handers.

In the absence of visual feedback, the perceived orientation of the fingers is systematically biased. In right-handers these biases are asymmetrical between the left and right hands in the horizontal plane and may reflect common functional postures for the two hands. Here we compared finger orientation perception in right- and left-handed participants for both hands, across various hand positions in the horizontal plane.

Perceived finger orientation is biased towards functional task spaces.

In the absence of visual feedback, the perceived position of the hands is systematically biased towards the plausible manual task space. Here we tested whether perceived orientation of the finger is similarly misperceived in right-handed individuals. Participants' index fingers were passively rotated about the middle joint to a range of test angles, either in the frontoparallel plane (Experiment 1) or the horizontal plane (Experiment 2); they reported perceived orientation of the finger by rotating a visual line presented on a screen optically superimposed on the location of their unseen finger.

The Subjective Visual Vertical and the Subjective Haptic Vertical Access Different Gravity Estimates.

The subjective visual vertical (SVV) and the subjective haptic vertical (SHV) both claim to probe the underlying perception of gravity. However, when the body is roll tilted these two measures evoke different patterns of errors with SVV generally becoming biased towards the body (A-effect, named for its discoverer, Hermann Rudolph Aubert) and SHV remaining accurate or becoming biased away from the body (E-effect, short for Entgegengesetzt-effect, meaning "opposite", i.e.

How our body influences our perception of the world.

Incorporating the fact that the senses are embodied is necessary for an organism to interpret sensory information. Before a unified perception of the world can be formed, sensory signals must be processed with reference to body representation. The various attributes of the body such as shape, proportion, posture, and movement can be both derived from the various sensory systems and can affect perception of the world (including the body itself).