Chapter 14

Chapter summary

The sensory systems do not automatically capture all of the information that is available in the sensory world. Instead they actively select only the information that is most useful to the task at hand, or potentially important for survival. The act of selection is called “paying attention”.

Perception is selective for two reasons. First, the brain is energy-starved, and cannot process all the sensory information it receives at once. Second, the problem of interpreting incoming signals is too difficult to solve in an exhaustive bottom-up fashion, and requires top-down selection in order to guide processing towards a solution.

Processing resources can select incoming information on the basis of its sensory modality, spatial location, time of occurrence, stimulus features, or association with specific objects or events. Two neural circuits in the frontotemporal cortex are crucial for attentional control of processing. The dorsal system controls goal-directed or top-down attention, and the ventral system controls stimulus-driven or bottom-up attention. Signals from these systems can influence neural activity at the lowest levels of processing in the sensory cortex.