Introduction to Cogsci April 07, 2005

Central Theme Cognitive Science was occuppied with the algorithmic level for much of its history: successive manipulation of semantically evaluable symbolic representations. Cognitive Science today: two major new trends:

The three levels Computational Algorithmic: input, computation, output Implementation One way of putting lesson from before: once you start to deal with real systems in real worlds, then things look different.

Clark’s problems with Marr Central problems, p. 85: Distinctions among levels not always clear Process of discovering should be deeply informed by neuroscience

Process of Discovery Biological evolution is liberated by being able to be mess –Hand case –Perceptual adaptation can be “motor specific” (87)

Interactive vision 88: 4 points

Mirror Neurons Mirror neurons and knowledge of other’s emotions

Mirror Neurons Fire in response to action in others Constitute in part a mirroring of a motor routine Connected to the limbic system and so to emotional reactions Explain potentially why facial imitation produces emotional synchronization

Summary “… the brain is revealed not as (primarily) an engine of reason or quiet deliberation, but as an organ of environmentally situated control.” (95)

Unclear Distinctions Among Levels Can get an upward cascade of influences in which isolating ‘the right task’ is problematic Many different levels of implementation Timing washes out in algorithmic description Biology need not give us neat decomposition

Reverse Engineering (Ch. 6) 2 examples in which behavior is revealed to have a basis very different from what one might have thought: –Cricket: does not have general representational and computational abilities; has special purpose strategies effective in environment. –Flocks of birds: no one has a plan, just three simple rules (108)