Decision-making due to a gradual ramp of neural firing rates?  Nope.  There are discrete state changes that are more informative that spike counts.

Single-trial spike trains in parietal cortex reveal discrete steps during decision-making
Kenneth W. LatimerJacob L. YatesMiriam L. R. MeisterAlexander C. Hukand Jonathan W. Pillow
Science 10 July 2015: 349 (6244), 184187. [DOI:10.1126/science.aaa4056]

About the Author

The Miller Lab uses experimental and theoretical approaches to study the neural basis of the high-level cognitive functions that underlie complex goal-directed behavior.