Your brain is created a human robot - is that your understanding.

a)    Chemical agents can cause damage to the cells in the brain, which can range from minor to severe. Effects of this type of brain damage can include memory loss, hallucinations (seeing false images), loss of senses, and even death. Finally, different diseases and conditions can lead to brain damage.
b)    In his previous work, Nicolas Schuck was able to show that the interactions between processes of learning, memory, and decision making are controlled by signals of the prefrontal cortex. ... Study participants solve decision tasks while their brain activity is measured via magnetic resonance imaging (MRI).

c)   subliminal. ... If you're worried, there's not much you can do, because subliminal literally means “below the threshold” or surface of your conscious mind, and you probably will never even notice that you're being controlled. Try reading only the capital letters of this definition for an example of a subliminal message.
d)    

the study of living organisms, divided into many specialized fields that cover their morphology, physiology, anatomy, behavior, origin, and distribution.

the plants and animals of a particular area.

"the biology of Chesapeake Bay"

the physiology, behavior, and other qualities of a particular organism or class of organisms.

"human biology"