The Predictive Brain: Perception Turned Upside Down

Accumulating evidence is turning the traditional picture of perception upside down and indicates that the brain works via the principles of predictive processing, in which the brain continuously attempts to predict its sensory input and its most probable causes, and compares these predictions to the actual sensory signals. The roots of the predictive brain paradigm stretch all the way back to Immanuel Kant’s philosophy. Now new advances and insights into brain activity and function, theoretical neuroscience, and artificial intelligence have finally cleared the ground for what Kant believed would become a Copernican revolution in cognitive science. If the predictive processing theories are correct, they should also be relevant for other animals, including fish. If that is so, what implications will this have for our interpretation of observations related to perception, cognition, and learning in fish? And how can these theories help us to better understand their qualitative experience of life and improve their welfare? In this chapter, we try to explore these questions, but we also look at what challenges a fish faces and why they are dependent on a qualitative perception of the world and themselves if they are to master them. Finally, we discuss how we should reinterpret our previous observations of fish behaviour and perception in the light of the predictive brain paradigm.