Symbiosis between human brain and emotion

BOOK REVIEW

By

Randeep Wadehra

The emotional life of your brain by Richard J. Davidson

Hachette. Pages: xviii + 279. Price: Rs. 499/-

In common parlance, emotion is used as synonymous with feeling. However, in psychology it indicates a reaction involving certain bodily changes, such as an accelerated or depressed pulse rate. Short-lived bodily change or distortion accompanies all emotional reactions. The three primary reactions of this type are anger, love, and fear, which occur either as an immediate response to external stimuli or are the result of an indirect subjective process, such as memory, association, or introspection. External stimuli diminish in importance, as a direct cause of a person’s emotional reaction, in proportion to the person’s maturity and as the stimuli develop more complexity. Here we are concerned with the symbiosis between human emotion and brain – which is this book’s main theme too. Davidson avers that prominent researchers in psychology declared that emotion disrupts cognitive function. But, since most of the research was done on “lab rats”, there were debates on the conclusions drawn by cognitive psychologists. 

Human brain is unquestionably the most sophisticated gizmo made by nature or any other agency – human or technological. The adult human brain is made up of approximately 100 billion neurons (nerve cells); neuroglia (supporting-tissue) cells; and other tissues. Neurons transmit and analyze all communication within the brain and other parts of the nervous system. Neuroglial cells are twice as numerous as neurons and provide structural support to the neurons. The brain appears as three connected parts: the cerebrum, the cerebellum, and the brain stem. Two other major parts, the thalamus and the hypothalamus, lie above the brain stem underneath the cerebellum. Most high-level brain functions take place in the cerebrum. The cerebrum receives information from the sense organs and sends motor commands (signals that stimulate activity in the muscles or glands) to other parts of the brain and the body. Many areas of the cerebral cortex (surface) correspond to specific functions, such as vision, hearing, speech, emotions, thinking, and remembering. The cerebellum coordinates body movements, especially voluntary movements, by fine-tuning motor commands from the cerebrum. The cerebellum also maintains posture and balance by controlling muscle tone and sensing limb positions. 

Of course, even as the contents of this tome refer to the physiological aspect, the focus remains on the psychological and emotional characteristics that emanate from, as well as affect, a person’s brain in different ways. Davidson contends that different people react differently to a given occurrence. This is because the individual mental make-up is unique; no two persons have identical emotional characteristics. Further, to establish the symbiosis between human brain and emotion, he quotes from the findings of Guido Gainotti, an Italian neurologist, who had studied patients with localized damage to their brains’ left or right hemispheres. Gainotti discovered that the damage had disabled the connection between their emotional expressions and external stimuli. For example, for no reason at all, they would laugh or weep when nothing funny or sad was happening around them. Perhaps, this is how researchers concluded that particular brain regions and brain networks generated specific emotions. 

The brain also has its inbuilt system of coping with extreme emotional situations. For example, when a death or setback generates negative emotions, the human brain as well as body immediately activate mechanisms to dampen the emotion and help regain equilibrium. This interesting book covers a huge spectrum of brain-emotion symbiosis in a well-argued and lucid manner. Obviously, the author has done extensive research on the subject. This should be of great interest to researchers as well as practitioners of psychology.

Published in The Financial World dated 02 August 2013