Experiencing sadness, disappointment, or ‘the blues’ from time to time is common. But depression is a mental illness where these feelings are prolonged and can cause significant physical and or mental harm.


Depression can manifest itself through a range of symptoms that can be intense, prolonged, distressing and upsetting to the person and their friends and family and, which can also interfere with daily life and relationships.


While depression is a serious mental illness, psycho-social treatment can help you recover.


Symptoms of depression can include:

  • A prolonged and persistent sense of sadness, emptiness or lowered mood
  • Loss of interest in activities that were previously enjoyable, such as socialising or hobbies. 


If these symptoms persist for more than two weeks, you may be suffering from depression and should seek diagnosis from a psychologist or GP.

More specific symptoms can also include the following although these can also vary:

  • Changes in appetite and/or weight gain or loss 
  • Difficulty sleeping or sleeping too much
  • Sluggishness or restlessness
  • Tiredness or loss of energy
  • Feelings of worthlessness or excessive guilt
  • Difficulty concentrating or making decisions
  • Decreased interest in sex
  • Thoughts of suicide or feeling that life is not worth living.

There is no one cause for depression. In some individuals, stressful life events such as the loss of a job, long-term unemployment, physical health issues, family problems, the death of a loved one, or the end of a close relationship can trigger depression. For other people, there is no obvious cause. 

Experts no longer believe that depression is caused by a chemical imbalance, but that the risk for developing depression is more likely to be related to a combination of a person’s genes, biology, life experiences, stress and thought processes.


Research suggests that for many people, genetics may play a part with around 30-40% of the risk for developing depression thought to be due to genetic factors. 


Research has found some differences in areas of the brain and brain activity that relate to emotional responses and emotion regulation, the interpretation of information (with a bias for negative information) and response to stress. Interestingly, many of these differences decrease with treatment. 

Stressful life events

Research suggests that the greater the number of stressful live events a person experiences, the greater their chances of developing depression. Early life stress and trauma can also increase the likelihood of developing depression later in life. 

How you think

People who tend to dwell on negative events, worry excessively, or hold a more negative view of themselves, the world, or the future, are more prone to depression. 

Depression is a common reason for people seeking help from mental health professionals. Research has shown that there are a number of effective psychological treatments for depression. The most effective psychological treatments for depression are cognitive behavioural therapy, problem-solving therapy, behavioural activation, and interpersonal psychotherapy. Mindfulness-based cognitive therapy has also been shown to be effective in preventing future depression in those people who have experienced depression before. 

Cognitive behavioural therapy (CBT)

CBT is a type of therapy that helps a person to change unhelpful thoughts and behaviours which can contribute to depression, and build skills to manage it. It is one of the most effective treatments for depression and can bring about lasting change that can decrease the risk for further depressive episodes. 

Problem-solving therapy

Problem-solving therapy helps people gain mastery over day-to-day difficulties, stresses and problems which otherwise might seem overwhelming. It has been shown to be effective in the treatment of depression.

Behavioural activation

It is common for people experiencing depression to feel too down, tired or unmotivated to take part in their usual activities. However the less a person does, the worse they can feel, and this can become a problematic cycle. In behavioural activation, activities and behaviour that can help to improve mood and quality of life are planned for in an ‘activity schedule’. Typically, a mix of activities are selected, including some which the person finds enjoyable and some which give them a sense of satisfaction and achievement. Behavioural activation has been found to improve mood and to be a particularly effective treatment for depression.  

Interpersonal psychotherapy (IPT)

IPT involves addressing problems in the person’s relationships and expectations about others that might be contributing to their mood, and has been found to be effective in the treatment of depression. IPT helps people to

  • find new ways to develop and nurture relationships
  • resolve conflicts with others
  • express emotions and communicate more effectively
  • adapt to changes in life roles
  • improve social support networks.

Mindfulness-based cognitive therapy (MBCT)

MBCT is an 8-week group-based program designed to reduce the risk of depression returning (relapse prevention), by teaching participants mindfulness meditation combined with cognitive-behavioural techniques. Mindfulness meditation helps the person to focus on the present moment without judging these experiences or trying to change them. MBCT has been found to be effective in preventing relapse, and there is some evidence that it may be effective as a treatment of depression as well. MBCT is also being offered as individual rather than group-based therapy however research on the effectiveness of this format is currently limited.

Short-term psychodynamic psychotherapy (STPP)

STPP focuses on how a person’s unconscious motivations may lead them to misinterpret situations and experiences, potentially contributing to their depressive symptoms. There are a number of different variations on the STPP model. Recent studies suggest that STPP may be effective in treating depression, however a key limitation is a lack of a definition around this therapeutic model and its key components, which makes researching the effectiveness of STPP and comparing studies, difficult.

Source: Australian Psychological Society (APS) website