Mental Representation

One way of expressing the aboutness of mental processes is to say that they involve representations — our thoughts represent possible state of affairs, our perceptions represent our immediate environment (generally, though not always, accurately).

The information processing approach in cognitive science Opens in new window and related constructs is built on the assumption that an organism’s ability to perceive, comprehend, learn, decide, and act depends on mental representations.

It is helpful to contrast a mental representation of an object with that of a physical external representation. Take a robin, for example.

Your mental representation of a robin codes information about the bird’s shape, size, coloring, and perhaps even its distinctive song. An artist’s drawing of a robin is an external representation of the real thing. It, too, may convey properly the bird’s shape, size, and coloring, but it would certainly lack its song.

Now, close your eyes and imagine a robin. You are using your mental representations of birds to create an image that only you can experience.

Some mental representations can be consciously experienced as images that are similar to visual, aural, and other kinds of perceptions. Unlike the artist’s sketch they cannot be observed by anyone but you.

Mental representations are private and are perceived, if at all, only by their owners. Not all mental representations are perceived as images, and their owners may not be conscious of them.

Even with the new technologies for examining the brain, scientists cannot read your thoughts because they cannot process your conscious or unconscious mental representations.

Dual properties

Just like non-mental symbols, mental representations have a dual aspect:

1. there is the representational vehicle on the one hand, which is the physical realization of the representation, and
2. the content on the other hand, which is what the representation is about.

In a non-mental example, the word “cat” and a picture of a cat are both about cats, but they represent cats with different vehicles.

Vehicular properties include both material properties (the medium) and (roughly) syntactic format properties. In our example, the word “cat” and the picture of a cat have the same content, but different formats and mediums.

• The word “cat” has a linguistic format, and is realized as ink on paper.
• The picture of a cat has an imagistic format and is realized on a photographic plate. Similarly, mental representations with the same content can have different vehicles.

The renowned psycholgoy philosopher Franz Brentano (1838-1917) further emphasized the dual quality of mental representations. Brentano believed that mental states comprise mental acts and mental contents. So, for example, my believing that Rosie, my pet cat, is lazy is a mental state—I am in the state of believing that Rosie is lazy.

For Brentano, the state has a dual character: it comprises an act, corresponding to the act of believing, and a content, namely the content that Rosie is lazy.

Brentano thought that mental states can differ even if they involve the same mental act. So, for example, my believing that Rosie is lazy, and my believing that all cats are lazy, would represent two different mental states. The same act is common to both, but the beliefs are differentiated by their content: one is about Rosie; the other about all cats.

Observing patterns of neural activity is not the same as experiencing mental representations.

Look again, in your mind’s eye, at the robin. Can you hear its songs?

Perhaps, but you will hear the real song of a robin only if you have acquired a mental representation of how a robin sounds. If you confuse it with the song of a cardinal or sparrow, that is because your mental representation is in error.

Mental representations, then, provide the basis for all cognitive abilities. To perceive your environment, you must compute mental representations of the objects around you and the events that are taking place.

To comprehend and learn from this literature, you must mentally represent the information that is conveyed through language. All that you know about the world, and your only basis for acting on the world, is found in your mental representations.