Anhedonia

Anhedonia can be of different types, depending on which aspect of the patient’s life it affects:

• Physical anhedonia is the loss of sensual and physical pleasure. People with this condition may not enjoy sex or food as much as they used to.
• Social or interpersonal anhedonia is marked by a loss of pleasure in or motivation to socialise, go out, connect with people, and form and maintain relationships. Some people with social anhedonia can keep up appearances, like looking happy at a party. But they tend to feel less happy at these gatherings than they used to.

Anhedonia can also be differentiated based on whether the activity that should have brought joy is ongoing or coming up soon:

• Consummatory anhedonia is the inability or reduced ability to take pleasure in things that are happening now.
• Anticipatory anhedonia is the impaired ability to enjoy something that is upcoming.

People with anhedonia may feel empty or numb or experience a loss of joy in things that used to bring them pleasure before. They are also more likely to feel negative emotions towards themselves and others. Some people with anhedonia are also more likely to diminish or underplay the memory of positive events.

That said, anhedonia isn’t just a feeling of unhappiness or emptiness for a short while, but a “near-complete” loss of joy in response to positive events and stimuli. It is accompanied by changes in the brain chemistry that disrupt the body’s natural rewards system to help you feel good. People with anhedonia have “persistently low motivation”. 

The symptoms of anhedonia can vary, depending on the type:

• Sexual anhedonia: Reduced or no feeling of pleasure during orgasm. Though sexual anhedonia can occur in females as well as males, it is reported more widely by men.
• Social anhedonia: Loss of pleasure or motivation to form interpersonal relationships and engage with people. While some people with this form of anhedonia may experience social withdrawal and discomfort in social situations, others may find themselves faking emotions.

Anhedonia is a trait or symptom rather than a disease in itself. It can arise in a number of situations, such as:

• In patients with:
  • Depression
  • Schizophrenia
  • Substance use disorder: Researchers have also seen anhedonia in the early stages of rehabilitation from alcohol use disorder, and recommend interventions to prevent these patients from spiralling into depression later
  • Post-traumatic stress disorder
  • Eating disorders such as anorexia nervosa
  • Parkinson’s disease
  • Anxiety

Risk factors for anhedonia can be genetic or environmental. Some risk factors for anhedonia are:

• Going through a traumatic event
• Having a major illness
• Experience of physical or sexual abuse
• Mental health disorders
• Females are more prone to anhedonia than males
• A family history of mental illness

Scientists at the US National Institutes of Health-affiliated National Institute of Mental Health did functional magnetic resonance imaging (fMRI) in 2,878 children aged 9-10. Of these,

• 261 children had anhedonia
• 277 low mood
• 109 anxiety
• 459 had attention-deficit hyperactivity disorder

The scientists found some characteristics of anhedonia which were different from the other conditions. Specifically, the children with anhedonia had a poorer association (hypoconnectivity) between the part of the brain responsible for arousal (the cingulo-opercular network) and the part responsible for dispensing rewards (the ventral striatum area) than in children who didn’t have anhedonia. Arousal and reward are obviously linked to motivation and anticipation/experience of joy.

Researchers have found that in people with depression and anhedonia, medicines such as anti-depressants and anti-psychotics don’t work as well as they typically do in people with depression but no anhedonia.

Anhedonia has also been linked with increased risk-taking behaviour and suicide risk.

To diagnose anhedonia, a psychologist or clinical psychiatrist would ask the patient about their symptoms and mood. He or she may also order a blood test to check for nutritional deficiencies and thyroid problems.

Treatment involves using medicines like anti-depressants and therapies such as:

• Electroconvulsive therapy: In which the doctor passes a small current through the patient's brain.
• Transcranial magnetic stimulation: This therapy uses a magnet to stimulate the nerves.
• Vagus nerve stimulation involves placing a small gadget in the body to stimulate the vagus nerve.

While these therapies may help some patients, it is useful to remember what research has shown: anhedonia can be very hard to get rid of. Where it accompanies depression, there have been cases where anhedonia (as a trait) has persisted even after a person's depression is treated. It is important to persist with therapy and support people who have anhedonia.