Lecture #7 looked at state machines.
Notes are available in four formats:
The lecture covered material from Chapter 5 of the textbook. Read through this, making sure you understand how the version of the wall following robot on pages 72-73 works.
The lecture did not cover Section 5.4 from the textbook (pages 77-79) and you do not need to cover it in your reading either.
The original paper on Elman networks is:
Elman, J.L. (1990). Finding structure in time. Cognitive Science, 14, 179-211.