Brain Eating Zombie of the Day

Terry Davidson, Director of American University's Center for Behavioral Neuroscience

Obese Brain May Thwart Weight Loss: Diets High in Saturated Fat, Refined Sugar May Cause Brain Changes That Fuel Overconsumption

I do not even have to enumerate your erroneous assumptions about animal models or the effects of diet- You failed Experimental Design 101. Remember that class? It's the one where they teach you about confounding factors. And experimenter bias.  And how to check the existing literature.

If you change two things in your test - fat and sugar content- You cannot tell which one caused the results you observe.
Period.

Luckily for us there is already plenty of data that these behavioral effects are caused by a high carbohydrate diet and the resulting hyperinsulinemia. And that a high fat diet actually lowers body weight and improves cognitive function.  

You're the Director?  You approve other people's projects?  That explains a lot.