I know, I know, Christmas is over, but it led me to thinking.

The Christmas trees in my sister Georgia’s family look like the picture above. My immediate family, on the other hand, gives one gift each or, by agreement, none at all. I give my daughter and her husband calendars. She gives me her best wishes. I gave my older grandson a new-born check up for an African baby and the younger one a money order.

True, I give Georgia and my niece more because they shower me with seven or eight gifts. This year, I managed to hit a home-run by giving an indigo-blue Turkish robe to Georgia. This was a milestone. The first gift I ever bought at age six was a China teacup and saucer with a lovely rose pattern. My mother wished aloud I had bought her stockings.

My sister and I had the same early conditioning about gift-giving at Christmas. We got a stocking with an orange and hard candy, one main gift, such as new ski pants or sweater and something small if it had been a prosperous year. Most were not and most years, my mother suffered torment, trying to stretch the money. She would wander the department store in despair.

Georgia was a single mother and yet, it was an article of faith with her that her girls had a big spread at Christmas. Our children, in a family with two employed,had to make do with a stocking, a main gift, an article of clothes and a book.

What is it, I wondered, that makes us so different now in spite of similar incomes. Were brain chemicals responsible?

It had been my good fortune to meet Dr. Brown, a UCLA psychiatric professor, who casually threw out the information that prescribing psychoactive medication was simple. You had to write a script for whichever brain chemical was missing.

Gamblers, for example, need dopamine. It is associated with anticipation or striving to achieve a goal and acts as a helping hand in such success. It triggers the reward centre and is associated with exuberance and desire, producing an excitable and talkative state. It enables a stressed out body to feel good. Chemically, it is a precursor to adrenaline as well as epinephrine and noreprinephrine. This last enables vigilant concentration and the fight or flight response, with a corresponding effect on the sympathetic nervous system. A serious deficit of dopamine can cause Parkinson’s Disease

Alcoholics, shopaholics, chocaholics need serotonin, the happiness drug, 80% of which is found in the gut. It enables nuerotransmission. It is triggered by feeling important and confident in the self. It falls off in the presence of loss and increases when we win.Too much serotonin can lead to “A powerful mix of intestinal and mental symptoms”, including hallucinations. (io9) I experienced this myself before the carcinoid in my ascending colon was diagnosed. The slow growing tumour produced high levels of the hormone. Whenever I lay down to sleep, I was racked by anxiety and nightmares, both of which cleared up after surgery. For the past 13 years, I have done a yearly test of my serotonin levels, with no evidence they are elevated.

Gaba is a chemical messenger, an inhibitory aid that reduces activity in the neurons the way brakes slow down a car. It acts the same as benzodiazepines, like librium, valium, lorazepam klonapin or atavin. It seems like just the thing for those who suffer anxiety. (I may be wrong. ) Oolong tea, meditating and yoga can achieve similar effects, we are told. Having tried, I say, “Tell it to the Marines.”

Finally, endorphins, another happiness chemical, is opiate-like and produced in the pituitary gland. It is triggered by physical actions, including exercise, and produces a feeling of euphoria or pleasure. Even seriously depressed people feel better for a long hike in nature. Obsessive compulsive behaviour may result from too few endorphins. One site muses that OCD people may never have been praised for achievement.

Happiness involves the presence of dopamine, serotonin, endorphins and oxycotin. The last is that wonderful drug that kicks in for most new mothers, establishing a bond with the baby. Some new mothers, doubting their own abilities, are astonished to feel this kick in.

At Christmas, Georgia and her family give themselves a license to shop. Unselfishly. Therefore serotonin. When they choose the right gift, often as a result of carefully listening to the recipient all year, they feel the dopamine of achievement. Thinking about those they are shopping for increases their oxytocin. If they actually walked the malls, I suppose, they might get a shot of endorphins, but probably someone will figure out that eBay serves a similar function. Then, of course, there is the oxytocin high of watching loved ones open the gifts.

Psychology Today says that happiness is a neurochemical spurt. Merry Christmases and Happy New Years ease us into winter here north of the equator. Now that I understand a little more, I hope can accept the generous bounty showered on me and let it carry me through to spring.