ABSTRACT
Recent neural network modeling supports a partial qualitative view of the prefrontal cortex developed over decades by Milner, Pribram, Nauta, and other neurobiologists. Two mutually paradoxical effects of frontal damage, namely cognitive perseveration and novelty preference, are explained by weakened gain of signals from motivational regions to sensory regions. Networks embodying such principles as adaptive resonance, synaptic gating, and opponent processing have been shown to simulate these effects. Such motivational-sensory linkage combines with planning and time-sequence organization into a role described by Pribram as that of “executive of the brain.” It is suggested that most functions needed for this executive can be modeled by suitable reconcatenation at many hierarchical levels of the same architectures used in our simulations, with two added mechanisms. The additions are the masking field and the avalanche, which serve to link perceptual and motor events across time.
