Types of mental illness - House with No Steps

Types of mental illness

Approximately half of Australia's population will experience a mental illness or disability at some stage of their life.

Different types of mental illness affect a person's thinking, emotional state and behaviours. 

A mental illness may disrupt a person's ability to work, carry out daily activities and have satisfying personal relationships. They can find it hard to take part in social activities and may experience sensory challenges.

A mental illness can be permanent, temporary or come and go.

Bipolar disorder

Bipolar disorder used to be known as manic depression, and causes extreme mood swings including emotional highs (mania) as well as extreme lows (depression). These mood swings come in ‘cycles’ which can last days, weeks or even months (Better Health Victoria).

How people with bipolar are feeling also doesn’t necessarily make sense in the context of what’s going on around them. Some people experience emotions such as uncontrollable crying or excessive happiness without a cause.

Bipolar can be very variable, however, when episodes are extreme, they can also bring on suicidal thoughts and symptoms of psychosis. The person may be affected so much that they are unable to distinguish reality from fantasy (Better Health Victoria).

The causes of bipolar disorder are not fully understood but are likely to be a combination of genetics and other causes.

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Clinical depression is a mental illness which significantly affects the way someone feels, causing a persistent lowering of their mood and feelings of dejection and loss.

Depression has a variety of symptoms and will affect everyone in different ways such as feeling extremely sad, disturbed sleep, loss of interest and motivation, feeling worthless, loss of pleasure in activities, anxiety, changes in appetite or weight, physical aches and pains and impaired thinking or concentration. Depression makes it more difficult to manage from day to day.

While the exact cause of depression isn’t known, it is generally due to a combination of recent events, other longer-term or personal factors, family history, drug and alcohol use, as well as changes within the brain itself.

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Stress or worry can be common feelings for many, but anxiety is when these feelings continue for a more significant period of time without a specific cause, and are often more extreme.

The main features of an anxiety disorder are fears or thoughts that are chronic and distressing, and often interfere with daily living. Other symptoms can include panic attacks, trembling, sweating, difficulty breathing, feeling faint, rapid heartbeat, nausea, or avoidance behaviour.

Some of the causes or triggers of anxiety include:

  • Environment
  • Stressful situations
  • History of anxiety in the family
  • Trauma
  • Physical health problems
  • Substance abuse

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Schizophrenia is a mental illness which influences the way a person thinks, feels, and acts, often distorting their perception of reality. People affected by schizophrenia have one ‘personality,’ just like everyone else. It is a myth that those with schizophrenia have a ‘split personality’. 

If not receiving treatment, people with schizophrenia may experience persistent symptoms of psychosis. They can have hallucinations such as seeing things that are not really there, hearing disembodied voices, smelling odours that do not exist, and feeling sensations on the skin even if nobody is touching you. They can also have delusions which are false beliefs that seem logical to the person, strongly persist in their mind, and refuses to go away.

Other signs and symptoms can include low motivation, dulled emotions, rambling and disorganised speech, lack of desire to form social relationships, and a lack of ability to express emotion.

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Anorexia nervosa

Anorexia nervosa is an eating disorder characterised by an abnormally low body weight, an extreme fear of gaining weight, and a distorted perception of body weight. People who have anorexia can restrict their eating, compulsively exercise, and misuse laxatives or diet aids, however, it is not connected to vanity or a lifestyle choice in any way. 

Anorexia has one of the highest mortality rates of all mental illnesses, with 10-20% of people dying within 20 years from complications or suicide.

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Bulimia nervosa

Bulimia Nervosa is a serious mental illness which involves binge-eating (consuming abnormally large amounts of food), followed by compensatory behavior such as vomiting, over exercising, fasting, or misuse of laxatives.  

The cycle of binge eating and purging/exercising, leads to intense feelings of guilt and shame for the person.  This mental illness often goes undetected because those with bulimia are normal weight or slightly overweight, and they often hide the behaviours associated.

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Obsessive compulsive disorder (OCD) 

Obsessive compulsive disorder (OCD) is an anxiety disorder where a person will experience thoughts and fears (obsessions) that lead to repetitive behaviours (compulsions). People with OCD are usually aware of the unreasonable nature of their obsessions and compulsions, however, feel unable to control it.  

Some common obsessions include:

  • Fear of germs, dirt, and poisons 
  • Fear of harm to yourself or others
  • Excessive concern with symmetry, exactness, and orderliness
  • Hoarding, or saving and collecting things

These obsessions lead to feelings of anxiety, disgust, and panic. Compulsions are the repetitive actions which are usually performed to prevent an obsessive fear from happening, to reduce anxiety, and to just make things feel right.  

Some common compulsions can include:

  • Excessive checking of items associated with safety such as locks and appliances
  • Excessive cleaning, washing, and showering
  • Touching, tapping or moving in a particular way or a number of times
  • Repeating words or numbers a certain number of times

Post-traumatic stress disorder (PTSD) 

Post-traumatic stress disorder (PTSD) is a mental illness which can develop after someone experiences or witnesses a traumatic event which threatened their life or safety, or that of others around them. For example, events which can trigger PTSD include a physical or sexual assault, an accident, natural disasters, or war.

Someone with PTSD may experience feelings of intense fear, panic, helplessness, or horror. They can re-live the traumatic event and feel intense emotional or physical reactions when reminded of the event such as sweating and heart palpitations.  Other symptoms include sleeping difficulties, lack of concentration, being easily startled, being constantly on the look out for danger, avoiding reminders of the event, and feeling emotionally numb.

It's not unusual for people with PTSD to experience other mental health problems at the same time such as depression, anxiety, and alcohol or drug use.

Impulse control disorder (ICD) and addiction

Impulse control disorder (ICD) is a class of disorders characterised by impulsivity and being unable to resist temptation which may harm oneself or others. For example, pyromania (deliberately starting fires), kleptomania (stealing), compulsive shopping, sexual compulsion (increased urge in sexual behavior and thoughts), and compulsive gambling are examples of impulse control disorders.

Addiction and substance abuse can be of a variety of legal and illegal substances such as alcohol, drugs, gambling, prescription medicines (pain killers or sedatives), inhalants such as household cleaners, and even internet usage. When someone becomes dependent, they can experience cravings or withdrawal symptoms when they stop.

Body dysmorphic disorder

Body dysmorphic disorder (BDD) is a mental illness where people constantly worry about the way they look. They can believe that minor or non-existent ‘flaws’, are actually serious defects in their appearance. It is however not related to vanity.

These perceived flaws cause the person substantial distress, and this obsession impacts their ability to function in daily life. People often obsess over their appearance and body image, repeatedly check the mirror, groom themselves obsessively, constantly diet and over exercise, and seek reassurance.

It’s not uncommon for people to seek out numerous cosmetic procedures to try to "fix" the perceived flaws, but are never satisfied.

Like many other mental illnesses, it's not known specifically what causes body dysmorphic disorder, and it is likely due to a combination of factors.

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