Now suppose that each higher level in the brain mainly reacts to the changes below it, but over some larger scale of time. If so, then when signals repeat at level A, the B-Brain will have nothing to say. And if the signals that go up to B form a sequence that repeats—so that the B-brain keeps seeing a similar pattern—then the C-Brain will sense a ‘constant condition,’ and thus have nothing to say to the level above it.
This could explain some common experiences because any repetitive signal would tend to partly ‘anesthetize’ the next level above it. So although your foot may continue to tap, most details of those smaller events won’t go up.
(Why might our brains have evolved to work this way? If some condition has been present for long—and nothing bad has happened to you—then it probably poses no danger to you; then so you might as well not pay attention to it and apply your resources more gainfully.)
However, this could also lead to other effects. Once a level gets freed from control by repetitive signals that come from below it, then it could start to send signals down to instruct those levels to try to detect different kinds of evidence. For example, during that railroad trip, perhaps you first heard those clacks on the tracks as forming a pattern of clack-clack-clack-clacks—that is, of beats in 4:4 time. Then you stopped hearing them at all—but soon you may have suddenly switched to hearing groups of ‘clack-clack-clacks’—that is, of beats in 3:4 time. What made you change your representation? Perhaps some higher level just switched to forming a different hypothesis.
Also, when repetitive signals anesthetize some parts of your brain, this could release some other resources to think in new, unusual ways. This could be why some types of meditation can thrive on repetitive mantras and chants. It also could contribute to what making some music so popular: by depriving the listener of some usual inputs, that repetitiousness could free higher-level systems to pursue their own ideas. Then, as suggested in §5-8, they could send down some ‘simuli’ to make some lower level resources simulate some imaginary fantasies.
Rhythmic and Musical Differences
“Music can move us through brief emotional states, and this can potentially teach us how to manage our feelings by giving us familiarity to transitions between the states that we know and thus gain greater confidence in handling them.”
Music (or art, or rhetoric) can divert you from your mundane concerns by evoking powerful feelings that range from delight and pleasure to sorrow and pain; these can excite your ambitions and stir you to act, or calm you down and make you relax, or even put you into a trance. To do this, those signals must suppress or enhance various sets of mental resources—but why should those kinds of stimuli have such effects on your feeling and thinking?
We all know that certain temporal patterns can lead to rather specific mental states; a jerky motion or crashing sound arouses a sense of panic and fear—whereas a smoothly changing phrase or touch induces affection or peacefulness.[118] Some such reactions could be wired from birth—for example, to facilitate relationships between infants and parents. For then, each party will have some control over what the other one feels, thinks, and does.
Subsequently, as we grow up, we each learn similar ways to control ourselves! We can do this by listening to music and songs, or by exploiting other external things, such as drugs, entertainment, or changes of scene. Then we also discover techniques for affecting our mental states ‘from inside’—for example, by thinking that music inside our minds. (This can have a negative side, as when you hear a person complain that they can’t get a certain tune out of their head.)
Eventually, for each of us, certain sights and sounds come to have more definite significances—as when bugles and drums depict battles and guns. However, we usually each have different ideas about what each fragment of music means—particularly when it reminds us of how we felt during some prior experience. This has led some thinkers to believe that music expresses those feelings themselves, whereas those effects are probably far less direct:
G. Spencer Brown: “[In musical works] the composer does not even attempt to describe the set of feelings occasioned through them, but writes down a set of commands which, if they are obeyed by the reader, can result in a reproduction, to the reader, of the composer’s original experience.[119]”
However, some other thinkers would disagree:
Marcel Proust: “Each reader reads only what is already inside himself. A book is only a sort of optical instrument which the writer offers to let the reader discover in himself what he would not have found without the aid of the book.”
Perhaps Felix Mendelssohn had something like this in mind when he said, “the meaning of music lies not in the fact that it is too vague for words, but that it is too precise for words.”
All of this raises questions that people seem strangely reluctant to ask—such why do so many people like music so much, and permit it to take up so much of their lives.[120] In particular, we ought to ask why nursery rhymes and lullabies occur in so many cultures and societies. In Music, Mind, and Meaning I suggested some possible reasons for this: perhaps we use those tidy structures of notes and tunes as simplified ‘virtual’ worlds for refining difference-detectors that we can then use for condensing more complex events (in other realms) into more orderly story-like scripts. See also §§Interior grounding.
Difference-Networks.
Whenever you want to accomplish some purpose, you will need to decide which things to change. To do this you’ll need to retrieve some knowledge about which actions that might help make those changes. But what should you do when what you have does not exactly match what you need? Then you’ll want to find some substitute that is different—but not too dissimilar.
Whenever you want to accomplish some goal, you will need to retrieve some knowledge about some actions or objects that might help. For example, suppose that you want to sit down, so you look for a chair, but none is in sight. However, if there were a bench in view, then you might regard it as suitable. What leads you to see the bench as similar—when you would not so regard a book or a lamp? What makes us selectively notice things that are likely to be relevant? Patrick Winston suggested doing this by organizing some bodies of knowledge into what he called “difference networks”—for example, like this:[121]
To use such a structure, one first must have some descriptions of the objects it represents. Thus a typical concept of a chair might involve four legs, a level seat, and a vertical back, in which the legs must support the seat from below at a proper height above the floor—whereas a bench is similar (except for being wider and not having a back).
118
In
120
One could ask the same questions about gossip, sports, and games. See
121
In his 1970 PhD thesis, Patrick H. Winston called this a “similarity network.” See [AIM xxx].