There is an increasing trend to explain emotions in terms of neurotransmitters. Neurotransmitters are chemicals that are found within the human being (this makes them endogenous substances) and are primarily responsible for the emotions we experience. The neurotransmitters are produced within the brain in response to whatever else is going on in our life. This increase in levels of a particular neurotransmitter is experienced as a particular emotion by the organism. Just like the increase, the deficiency of a particular neurotransmitter is noticed by the organism and is also experienced as emotion.

This can be explained well through this image

So, to answer your question very simplistically, to add emotions to a robot, you would need the chemicals mentioned above

However, as you obviously understand, the problem is more complicated than that.

This just explains what chemicals are behind the emotions we experience. That is not enough to make a robot experience emotions.

The key question then is not ‘How we feel the feelings’ but ‘Who feels the feelings’.

Obviously, it is the “who” which is missing in the robot. The robot can have the chemicals but unless it has the ‘self’ that experiences those emotions, there is no-one who feels the feelings.

On to the search of the Self.

When we look inward, we don’t find a solid sense of a ‘self’ or a ‘driver’, so to speak. If we are able to get fleeting images and mental sounds out of the way, there is merely a sense of falling. What is the essential you-ness or me-ness is very hard to grasp. It’s like trying to catch a fistful of water.

It is very difficult to establish who or what the “see-er” is. It cannot be a self in the sense of a smaller ‘me’ sitting inside my head, driving me around and seeing the world through my eyes. This idea (called homunculus) is a fallacy because there is must be an ever litter-er me sitting inside the little-me and there much be an even-more-little-me inside that litter-er me and so on and so forth.

Where does the me-ness in me or the you-ness in you come from?

That’s a difficult question to answer. So, let us go deeper by considering these points.

1. Split Personality Disorders – These occur when several selves are found living in the same physical body. It’s a documented medical condition. What do they tell us about what the “self” is? If more than one self can exist in the same body, then self is merely a mental construct. Even we are different selves with different people, its just that, in a person with this disorder, these selves become separated and are unaware of each other with a different bag of experiences, memories and beliefs
2. Amnesia, Dementia or Alzheimer – People who have these become (in some cases slowly) unrecognizable. Exactly what gets destroyed in these diseases. When do we say that the person is not “themselves” anymore? Or is it very difficult to say that? Is it really just memory, or is there something else?
3. Is there a physical self? As far as I have read, there is no place in the brain which can be called the center of the self or where the self “sits” (or maybe we just haven’t found it yet) Then is the self like the internet? It’s a conceptual construct that does exist but is difficult to pin-point
4. Animals behave fairly consistently with each other? How do theyrecognize their selves and others? When do they consider the other person or animal as “not the same”? Do we know what their criteria is?
5. What about the familiar contender, the ‘soul’? I believe, the soul is merely redefining the problem from a tangible body to an intangible one. But we are left with the core problem.

There are two thought-experiments I read about that I am reminded of which address this confusing topic of self, Two riddles actually. Let me share them with you

• If there is ship called “Queen of the Sea” and she is in a bad shape because of years of use. We bring her into a harbor and start replacing the parts one by one. Over the next few visits, we change each and every part of the ship. Now, the ship has not even a single part that was there in the original ship. The question is – is it still the same ship? Is it still “Queen of the Sea” and if yes, what makes it so?
• If I divide my brain into two and put them in two different bodies. And if both bodies come alive, which one is the real me?

Our experience of life is seamless, consistent and smooth.

Unless we stop to think about it.

The mystery lives.

PS1: There is a very interesting side-note to neuro-transmitters.

Very interestingly, it is also possible to become addicted to these chemicals (just as you could get addicted to cocaine or nicotine). In fact, the receptors that cells use to receive these neurotransmitters are the same that they use to receive chemicals like cocaine or nicotine.

And remember, all drugs of abuse cause a powerful surge of dopamine. The likelihood of one becoming addicted to a drug that releases dopamine depends upon the speed of the release, the intensity of that release, and the reliability of that release.

While, you have to visit a friendly, neighborhood drug dealer to get your dose of cocaine, if you are addicted to a particular neurotransmitter – you can get a ‘fix’ by repeatedly creating situations in your life which would warrant the ‘release’ of the chemical in your brain. Could this be the reason why so many of us repeat emotional dramas and patterns in our life.

(I paraphrase the above from memory, and welcome corrections)

P.S2: Chemistry of life image, seen on  http://medicalhumour.wordpress.c…

Recommended Reading (on the search of self): The Ego Trick by Julian Baggini