But because of the way in which depictions represent, there is a correspondence between parts and spatial relations of the representation and those of the object; this structural mapping, which confers a type of resemblance, underlies the way images convey specific content. In this respect images are like pictures. Unlike words and symbols, depictions are not arbitrarily paired with what they represent.
A mental image occurs when a representation of the type created during the initial phases of perception is present but the stimulus is not actually being perceived; such representations preserve the perceptible properties of the stimulus and ultimately give rise to the subjective experience of perception.
These organizational processes result in our perceptions being structured into units corresponding to objects and properties of objects. It is these larger units that may be stored and later assembled into images that are experienced as quasi-pictorial, spatial entities resembling those evoked during perception itself.... It is erroneous to equate image representations with mental photographs, since this would overlook the fact that images are composed from highly processed perceptual encodings.
Like pictures, images seem to depict information about interval spatial extents. The scanning experiments support the claim that portions of images depict corresponding portions of the represented objects, and that the spatial relations between portions of the image index the spatial relations between the corresponding portions of the imaged objects.
It is hard to define something one knows little about
Physics seems to have done reasonably well in studying electrons, although there is not to this day a precise definition of this term.
Mr. Magoo Rule: Text and graphics must be easily distinguished and recognized. Don ́t make your audience members feel like the vision challenged Mr. Magoo—viewers of an electronic slideshow should not risk eyestrain!
Resist the temptation to use special effects. Think about science fiction movies with lots of special effects: If you notice that special effects are special effects, they will fail.
Bullets are a convenient way to present the separate elements of a list. However, bullets are a bit like salt—often essential to bring out the best, but distasteful if overdone.