Perception and cognition can be understood either as conscious
experience, thought, and behaviour or as bodily functions executed
at the level of information processing. Whether or not they are
cognitively penetrable depends on the level referred to. Selective
attention is the mechanism by which cognition affects perception,
theory influences observation and observational reports, culture
biases experience, and current knowledge determines what inferences
are made. Seeing must be distinguished from seeing
as.