Two mechanisms have been commonly described which allow us to locate objects in space. Direct perception occurs when we see, hear or feel an object; by directly looking at an object, for example, we can easily describe its size, shape and where it is located in space. However, when an object is not directly in front of us, we need to rely on a higher-level mental process known as visualization to help us recreate the object's location. An everyday example of visualization is reading a map; a map can tell us where a particular landmark is, even if that landmark is not in our direct line of sight. In a new report in Current Directions in Psychological Science, a journal of the Association for Psychological Science, Roberta L Klatzky, Bing Wu and George Stetten of Carnegie Mellon University suggest that we can locate objects in space by accurately combining features from perception and visualization. The resulting spatial representation is called amodal, because it is independent of any particular sensory experience, like vision. The use of ultrasound technology provides an everyday context where people need to combine information from direct perception and visualization, and the authors used this technology for their experiments.
Ultrasound works by using sound waves to generate images through soft tissue. A transducer (a probe that is passed along the skin) sends out sound waves below the skin's surface. As the sound waves encounter sound-reflecting objects (such as organs), echoes are sent back to the transducer. These echoes are converted into 2-D images, showing us on a monitor what the objects look like. Doctors are increasingly relying on ultrasound technology to help guide them in a number of surgical procedures, such as placing peripheral catheters and performing breast biopsies. As doctors become more and more reliant on ultrasound, it becomes more important to fully understand and improve use of this technology.
One of th
'/>"/>
| Contact: Barbara Isanski bisanski@psychologicalscience.org Association for Psychological Science Source:Eurekalert |