Depression is a complex of psychological and physical symptoms. Low mood level or sadness is often the most prominent symptom. The common property of these symptoms is a decreased activity level in parts of the brain.
THE SYMPTOMS OF DEPRESSION
Depression may give one or more of these symptoms:
-Low mood level or sadness.
-Lack of joy or interest in activities that were joyful before.
-Pessimism.
-Feel of guilt of something without any substantial reason to feel so.
-Inferiority thoughts.
-Irritability.
-Slowness in the thought process.
-Slowness in interpreting sensorial stimuli.
-Slowness of digestion or other internal physical processes, and symptoms caused by this slowness, for example inflated stomach, constipation or difficulties by urination.
-Slow physical reactions.
Depression can be a mild disease that only causes some annoyance in the daily life, but can also get very serious and make a person totally unable to work and unable to participate in social life. By depression of some severity, there is also a greater risk of suicide.
Depression can occur in all age classes. In teenagers lack of interest in school work, withdrawal from social life and difficult mood can be signs of depression.
THE PHYSIOLOGICAL CHANGES THAT PRODUCE THE SYMPTOMS
By depression there is a decreased amount of neurotransmitters in parts of the central nervous system, mainly deficiency of serotonin, but also to some extend of noradrenalin, acetylcholine, dopamine or gamma-amino-butyric acid (GABA), or the nerve cells do not react properly by stimulation from neurotransmitters. A neurotransmitter is a signal substance that transmits the nerve signal through the junctions between two nerve cells.
Serotonin and noradrenalin cause nerve cells to send impulses along to other nerve cells, and thus increase the activity in the brain. Deficiency of these substances causes slowness in parts of the brain, and that again causes the depressive symptoms.
The role of GABA is the opposite, namely to slow down some nerve impulses, mainly those causing anxiety and panic response. Lack of GABA causes higher anxiety and easier panic response. Yet, lack of this transmitter also seems to cause depressive symptoms. This is because a too high activity in some brain processes may slow down other processes.
There are many causes and subtypes of depression with different physiological mechanisms involved.
TYPES OF DEPRESSION
Depression is often divided into subtypes according to exhibited symptoms.
1. Mono-polar depression and dysthymic disorder
By mono-polar depression there are pure depressive symptoms. Mild cases of mono-polar disorder that do not affect a persons ability to work and to participate in social activities are often called dysthymic disorder.
2. Bipolar disorder (manic-depressive disease) and cyclothymic disorder
In this condition there are periods with symptoms of depression – the depressive phase, alternating with periods of elevated mood level with increased mental and physical activity – the manic phase. In the manic phase, the affected person also sleeps poorly and has concentration difficulties. A mild form of this disease is called cyclothymic disorder.
3. Manic disorder
This condition is characterized by abnormally elevated mood, by unrealistic optimism, by lack of sleep and by hyperactive behaviour. Many psychiatrists think that this disorder is simply the same disease as bipolar disorder where the depressive face has not yet occurred.
4. Depression with mainly physical symptoms
Sometimes the physical symptoms of depression are alone or dominant, as for example: Digestive problems, constipation, difficulties with urination, slow response to sensorial stimuli or slow physical reactions.
THE SYMPTOMS OF DEPRESSION
Depression may give one or more of these symptoms:
-Low mood level or sadness.
-Lack of joy or interest in activities that were joyful before.
-Pessimism.
-Feel of guilt of something without any substantial reason to feel so.
-Inferiority thoughts.
-Irritability.
-Slowness in the thought process.
-Slowness in interpreting sensorial stimuli.
-Slowness of digestion or other internal physical processes, and symptoms caused by this slowness, for example inflated stomach, constipation or difficulties by urination.
-Slow physical reactions.
Depression can be a mild disease that only causes some annoyance in the daily life, but can also get very serious and make a person totally unable to work and unable to participate in social life. By depression of some severity, there is also a greater risk of suicide.
Depression can occur in all age classes. In teenagers lack of interest in school work, withdrawal from social life and difficult mood can be signs of depression.
THE PHYSIOLOGICAL CHANGES THAT PRODUCE THE SYMPTOMS
By depression there is a decreased amount of neurotransmitters in parts of the central nervous system, mainly deficiency of serotonin, but also to some extend of noradrenalin, acetylcholine, dopamine or gamma-amino-butyric acid (GABA), or the nerve cells do not react properly by stimulation from neurotransmitters. A neurotransmitter is a signal substance that transmits the nerve signal through the junctions between two nerve cells.
Serotonin and noradrenalin cause nerve cells to send impulses along to other nerve cells, and thus increase the activity in the brain. Deficiency of these substances causes slowness in parts of the brain, and that again causes the depressive symptoms.
The role of GABA is the opposite, namely to slow down some nerve impulses, mainly those causing anxiety and panic response. Lack of GABA causes higher anxiety and easier panic response. Yet, lack of this transmitter also seems to cause depressive symptoms. This is because a too high activity in some brain processes may slow down other processes.
There are many causes and subtypes of depression with different physiological mechanisms involved.
TYPES OF DEPRESSION
Depression is often divided into subtypes according to exhibited symptoms.
1. Mono-polar depression and dysthymic disorder
By mono-polar depression there are pure depressive symptoms. Mild cases of mono-polar disorder that do not affect a persons ability to work and to participate in social activities are often called dysthymic disorder.
2. Bipolar disorder (manic-depressive disease) and cyclothymic disorder
In this condition there are periods with symptoms of depression – the depressive phase, alternating with periods of elevated mood level with increased mental and physical activity – the manic phase. In the manic phase, the affected person also sleeps poorly and has concentration difficulties. A mild form of this disease is called cyclothymic disorder.
3. Manic disorder
This condition is characterized by abnormally elevated mood, by unrealistic optimism, by lack of sleep and by hyperactive behaviour. Many psychiatrists think that this disorder is simply the same disease as bipolar disorder where the depressive face has not yet occurred.
4. Depression with mainly physical symptoms
Sometimes the physical symptoms of depression are alone or dominant, as for example: Digestive problems, constipation, difficulties with urination, slow response to sensorial stimuli or slow physical reactions.
