User:Kate Hardin/sandbox

Assessment[edit | edit source]
In a mental rotation test, the subject is asked to compare two 3D objects (or letters), often rotated in some axis, and state if they are the same image or if they are mirror images (enantiomorphs). Commonly, the test will have pairs of images each rotated a specific amount of degrees (e.g. 0°, 60°, 120° or 180°). Some pairs will be the same image rotated, and others will be mirrored. The subject will be shown a set number of the pairs. The subject will be judged on how accurately and rapidly they can distinguish between the mirrored and non-mirrored pairs.

Shepard and Metzler (1971)
Roger Shepard and Jacqueline Metzler (1971) were some of the first to research the phenomenon. Their experiment specifically tested mental rotation on three-dimensional objects. Each subject was presented with multiple pairs of three-dimensional, asymmetrical lined or cubed objects. The experiment was designed to measure how long it would take each subject to determine whether the pair of objects were indeed the same object or two different objects. Their research showed that the reaction time for participants to decide if the pair of items matched or not was linearly proportional to the angle of rotation from the original position. That is, the more an object has been rotated from the original, the longer it takes an individual to determine if the 2 images are of the same object or enantiomorphs.

Vandenburg and Kuse (1978)
In 1978, Steven G. Vandenberg and Allan R. Kuse developed a test to assess mental rotation abilities that was based on Shepard and Metzler’s (1971) original study. This test was constructed using India ink drawings. Each stimulus was a two-dimensional image of a three-dimensional object drawn by a computer. The image was then displayed on an oscilloscope. Each image was then shown at different orientations rotated around the vertical axis. Following the basic ideas of Shepard and Metzler's experiment, this study found a significant difference in the mental rotation scores between men and women, with men performing better. Correlations with other measures showed strong association with tests of spatial visualization and no association with verbal ability

Neural Activity during Mental Rotation [edit | edit source]
In 1999, a study was conducted to find out which part of the brain is activated during mental rotation. Seven volunteers (four males and three females) between the ages of twenty-nine to sixty-six participated in this experiment. For the study, the subjects were shown eight characters 4 times each (twice in normal orientation and twice reversed) and the subjects had to decide if the character was in its normal configuration or if it was the mirror image. During this task, a PET scan was performed and revealed activation in the right posterior parietal lobe.

Functional magnetic resonance imaging (fMRI) studies of brain activation during mental rotation reveal consistent increased activation of the parietal lobe, specifically the inter-parietal sulcus, that is dependent on the difficulty of the task. In general, the larger the angle of rotation, the more brain activity associated with the task. This increased brain activation is accompanied by longer times to complete the rotation task and higher error rates. Researchers have argued that the increased brain activation, increased time, and increased error rates indicate that task difficulty is proportional to the angle of rotation