Cajal"s research resulted in abandonment of neural net theory in favor of neuron doctrine. Edgar adrian: recorded electrical signals from single sensory neurons. all a c ti o n p o t e n ti al s a r e b a si c ally t h e s a m e. Brain i maging: cr e a t e i m a g e s t o s h ow a c ti v e a r e a s of b r ai n. Let s yo u k n ow w hi c h a r e a is a c ti v e . www. notesolution. com. Functional magnetic resonance imaging (fmri): m easure blood flow wi thout radioactive t racers. Takes advantage that he moglobin has m agnetic proper ties. Deter mines relative activity of areas b detecting changes in the m agnetic response of the he moglobin.