Biomedical subjects

M O Ernst

Publications and source records attributed to M O Ernst.

3 recordsLinked to original sources

PubMed2002

Combining sensory information: mandatory fusion within, but not between, senses.

Humans use multiple sources of sensory information to estimate environmental properties. For example, the eyes and hands both provide relevant information about an object's shape. The eyes estimate shape using binocular disparity, perspective projection, etc. The hands supply haptic shape information by means of tactile and proprioceptive cues. Combining information across cues can improve estimation of object properties but may come at a cost: loss of single-cue information. We report that single-cue information is indeed lost when cues from within the same sensory modality (disparity and texture gradients in vision) are combined, but not when different modalities (vision and haptics) are combined.

Cues↗

PubMed2001

Viewpoint dependence in visual and haptic object recognition.

On the whole, people recognize objects best when they see the objects from a familiar view and worse when they see the objects from views that were previously occluded from sight. Unexpectedly, we found haptic object recognition to be viewpoint-specific as well, even though hand movements were unrestricted. This viewpoint dependence was due to the hands preferring the back "view" of the objects. Furthermore, when the sensory modalities (visual vs. haptic) differed between learning an object and recognizing it, recognition performance was best when the objects were rotated back-to-front between learning and recognition. Our data indicate that the visual system recognizes the front view of objects best, whereas the hand recognizes objects best from the back.

Adult↗

PubMed2000

Touch can change visual slant perception.

The visual system uses several signals to deduce the three-dimensional structure of the environment, including binocular disparity, texture gradients, shading and motion parallax. Although each of these sources of information is independently insufficient to yield reliable three-dimensional structure from everyday scenes, the visual system combines them by weighting the available information; altering the weights would therefore change the perceived structure. We report that haptic feedback (active touch) increases the weight of a consistent surface-slant signal relative to inconsistent signals. Thus, appearance of a subsequently viewed surface is changed: the surface appears slanted in the direction specified by the haptically reinforced signal.

Biofeedback, Psychology↗