Depression is very common – it is estimated that at least one in five people in Ireland will develop depression during their lifetime.
Depression is not to be confused with the normal ups and downs of everyday life. Everyone can feel a bit ‘down’ from time to time as a reaction to an upsetting event, but will start to feel better after a few days or weeks. It is a natural, short-lived response to stressful times in life.
However, some people are unable to escape this low mood, and find it difficult to carry on with life as usual. They may experience low/sad, irritable or indifferent mood, loss of interest and enjoyment in daily life and a general lack of energy. This may be often accompanied by some or all of the following physical symptoms, fatigue and reduced activity, disturbed sleep or excessive sleep, changes in appetite and weight, loss of sex drive, unexplained aches and pains e.g. headache, backache and changes to the menstrual cycle.
Depression affects different people in different ways – not everyone has the same symptoms. Other symptoms include poor concentration or reduced attention, difficulty in making decisions, tearfulness, restlessness, agitation or anxiety, low self-confidence and self-esteem, feelings of guilt, inability to cope with life as before, avoiding other people, bleak view of the future, morbid thoughts, ideas of self-harm.
Treatment is available and recovery is possible.
Starting in the 1960’s neuroscientists regarded depression as a kind of ‘anaemia’ in the brain – a lack of three important neurotransmitters serotonin, dopamine and noradrenaline in key emotional regions in the brain. Antidepressant drugs were then developed to bring the levels of these neurotransmitters particularly serotonin back to normal. Prozac is a good example of this type of drug and it has proved to be a safe and effective life saver for many the depressed patient.
However, recently neuroscientists have had a radical change of mind with respect to the nature of depression. This change of view is partially due to evidence from brain imaging studies in depressed patients showing dramatic changes in nerve activity in the frontal lobe of the brain.
The importance of the frontal lobe in depression
Nervous activity in the frontal lobes forms our attitudes, plans and strategies and is at least in part under our own control. This view advocates that depression is in fact a disorder of thinking – a sort of obsessional pessimism from which the depressed patient can see no way out and this is what causes the low neurotransmitter levels.
The WISCONSIN STUDY adds another twist by showing that the brains of depressed individuals actually exhibit the same initial levels of activity in positive/pleasure-generating brain regions. Instead they found differences in the ability to sustain those positive emotions.
Findings from my own research group and others show that three important neurotransmitters serotonin, dopamine and noradrenaline play a key role in sustaining attention and motivation the brain. Thus low neurotransmitter levels may impair the ability to ‘embed’ these new thoughts and emotions leaving the depressed patient feeling like they are back at square one. This study lends support to notion that depression is best treated by psychological/behavioral treatments or in combination of drugs, not drugs alone.
Thus while antidepressants can help treat the chemical anaemia – good mental heath in particular careful monitoring of your everyday thoughts and attitudes will ensure that negative thoughts are nipped in the bud is also vital in the treatment and even the prevention of depression.