FIGURE 11.

(A) A gated dipole opponent process in a value category can generate habituative ON responses and transient OFF rebounds in response to phasic cue onset and offset, respectively. See text for details. (B) A READ (REcurrent Associative Dipole) circuit is a gated dipole with excitatory feedback, or recurrent, pathways between activities x₇ and x₁, and activities x₈ and x₂. Sensory representations S_k send∖conditionable signals to the READ circuit that are gated by conditioned reinforcer adaptive weights, or long-term memory (LTM) traces, w_k7 and w_k8 to the ON and OFF channels, respectively. Read-out of previously learned adaptive weights is dissociated from read-in of new values of the learned weights. This dissociation allows new weight learning to be generated by teaching signals from the ON or OFF channel that wins the opponent competition. The combination of recurrent feedback and associative dissociation enables the adaptive weights to avoid learning baseline noise, while they maintain in short-term memory the relative balance of ON and OFF channel conditioning during a motivated act, and preserve their learned conditioned reinforcer associations until they are disconfirmed by predictive mismatches if and when new learning contingencies are experienced. (C) When the tonic arousal level is chosen between low and high values, an Inverted-U in gated dipole responsiveness is caused. At low arousal levels, an underaroused depressive syndrome occurs. At overaroused arousal levels, an overaroused depressive syndrome occurs. See text for details. [Reprinted with permission from Grossberg and Schmajuk (1987).]