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Lee and Mumford interpret the visual pathway in terms of Bayesian belief propagation: each stage in the processing uses output from the one further up as contextual information and output from the one further down as evidence to update its belief and corresponding output.

Each layer thus calculates probabilities of features of the visual display given noisy and ambiguous input.

Verschure summarizes version VII of his distributed adaptive control model as "a unifying theory" of perception cognition, and action. He states that it uses a learned world model in its contextual layer which biases perception processing (top-down) on the one hand, and saliency (bottom-up) on the other. Between these to appears to be what he calls the validation gate which defines matching and mismatch between world model and percepts.

Neurons that receive auditory and visual ascending input also receive (only) auditory and visual descending projections.

Deco and Rolls introduce a system that uses a trace learning rule to learn recognition of more and more complex visual features in successive layers of a neural architecture. In each layer, the specificity of the features increases together with the receptive fields of neurons until the receptive fields span most of the visual range and the features actually code for objects. This model thus is a model of the development of object-based attention.

Yu and Dayan argue that uncertainty should suppress top-down, context-dependent factors in inference, and strengthen learning about the situation.

The cognitivist interpretation of the terms 'bottom-up' and 'top-down' is that of hypothesis-driven or expectation-driven processing., respectively.

The anatomical interpretation of the terms 'bottom-up' and 'top-down' is that of feedforward vs. feedback connections in a processing hierarchy, respectively.

The terms 'bottom-up' and 'top-down' can mean different, related things depending on context. Engel et al. list four:

  • anatomical
  • cognitivist
  • gestaltist
  • (neural) dynamicist

Grossberg's ART and Friston's theory of cortical responses appeal to the anatomical interpretation of 'top-down' and 'bottom-up' processing and stress feedback as well as feedforward connections.

Neurons at low stages in the hierarchy of visual processing extract simple, localized features.

Saccade targets tend to be the centers of objects.

Contrast sensitivity is an important feature of early visual processing.

Both populations in prefrontal cortex and posterior parietal cortex show correlates of bottom-up and top-down visual attention.

Visual attention is influenced both by local and global saliency, ie. bottom-up processes, and by semantics, ie. top-down processes.

Low-level (dis)similarity is important for top-down visual search.

The biased competition theory of visual attention explains attention as the effect of low-level stimuli competing with each other for resources—representation and processing. According to this theory, higher-level processes/brain regions bias this competition.

Early theories which assume that higher-level brain regions form hypotheses about the world and that top-down, or feedback connections carry predictions for low-level stimuli derived from these hypotheses is Grossberg's ART.