The results from mental rotation experiments seem to indicate that the time it takes to complete mental rotation:

Mental rotation is the capacity to revolve mental descriptions of two-directional and three-directional purposes as it is associated with the visible image of this circumrotation in the individual brain. Roger Shepard and Jacqueline Metzler (1971) were those who researched on this.

Their research clearly examined mental rotation on three-directional things. Per discussion was done with many combinations of three-directional, without any lined objects. The research was intended to estimate how much time it would carry specific case to decide that a couple of things were certainly the identical thing or two distinct things.

Their analysis revealed that the reaction interval for shareholders to determine if the set of things balanced or not was linearly equivalent to the edge of revolution from the initial state. If the object is more rotated from its original position then the time would be taken more to detect by a man regarding images.  

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