Synesthesia: II. Psychophysical relations in the synesthesia of geometrically shaped taste and colored hearing

The psychophysical function in two synesthetic subjects, one with geometrically shaped taste and the other with colored hearing, is investigated. Each synesthete is compared with three control subjects. Pilot studies are used to construct appropriate response domains. Compared to controls, synesthetes give a restricted set of responses that are also asymmetric with respect to the range of choices available in various subsets of the response domain. A combination of absolute and relative effects is also distinctive of synesthetic percepts. It is concluded that synesthesia is a distinct phenomenon unlike ordinary mediated associations, and occupies an intermediate position in the range of simple to complex brain mechanisms.     

Planning and acting

A new theory of problem solving is presented, which embeds problem solving in the theory of action; in this theory, a problem is just a difficult action. Making this work requires a sophisticated language for-talking about plans and their execution. This language allows a broad range of types of action, and can also be used to express rules for choosing and scheduling plans. To ensure flexibility, the problem solver consists of an interpreter driven by a theorem prover which actually manipulates formulas of the language. Many examples of the use of the system six given. including an extended treatment of the world of blocks. Limitations and extensions of the system are discussed at length. It is concluded that a rule-based problem solver is necessary and feasible, but that much more work remains to be done on the underlying theory of planning and acting.     

Rules and topics in conversation

Rules of conversation are given that specify what can follow what. A system for deciding what makes a reasonable subject for a conversation is shown. Topics are discussed and rules for topic shift are presented.     

Recall failure following successful generation and recognition of responses by alcoholic Korsakoff patients

Amnesic Korsakoff patients and controls were presented with twelve words, each shown individually in the presence of a weak associate. They were then asked to freely associate to 12 other words that were strong associates of the to-be-remembered (TBR) words. The Korsakoff patients generated, and were able to recognize, as many of the TBR words as the controls. Yet, in spite of this recognition ability, these same patients were subsequently unable to recall the critical TBR words when the weak cues were again presented. A follow-up study found that the same recognition results could be obtained with Korsakoffs months after initial presentation suggesting that the patients might initially have “recognized” the most highly associated words simply because they represented the most probable choices. Intermediate association prompts failed to generate correct responses. It was hypothesized that the Korsakoff patients cannot restructure their semantic associative hierarchy during input in such a way as to become sensitized to other than the strongest associates as prompts during recall.