Fear Unveiled- the science behind phobias

Mind.com defines a phobia as “A type of anxiety disorder, an extreme form of fear or anxiety, triggered by a particular situation or object”. Whilst everyone experiences fear in their lives, phobias refer to a heightened and usually irrational response to specific stimuli- often affecting daily life.

According to psychology, there are five main types of phobias. This includes animal phobias, environmental phobias (height, large entities of water etc), injection/blood phobias, situation phobias (like going to the dentist) and a category for everything else imaginable.

So, what causes phobias? Unfortunately, this still isn’t fully understood- however, research does suggest that genetics may be involved. Twin studies are particularly useful in this field: given that identical twins share the same DNA, if one has a genetic condition the other is likely to suffer from it too. This principle extends to phobias- studies on twins raised separately reveal a higher incidence of shared phobias. More specific research revealed that when one twin experiences agoraphobia (fear of situations/places where escape may be difficult or not possible), the likelihood of the second twin developing the same phobia is 39%. Additionally, many phobias develop as a result of a traumatic experience- a common scenario involves someone being attacked by a dog during childhood, which can lead to a lasting fear of dogs. Other theorised causes include learned behaviours, where children observe parents with specific phobias and adopt similar fears and responses, as well as chemical imbalances and drug use.

The majority of understanding about the neuroscience of phobias actually comes from animal research- mainly conducted with lab rats. Researchers employ a fear conditioning/fear extinction model where rats are conditioned to fear a specific stimulus (such a noise/sound) by associating it with an electric shock. Then, scientists work to “extinguish” this fear by continuously exposing the rats to the sound without the shock. With the use of electrodes, researchers can record and analyse the electrophysiological activity in the brain.

Using this technique, researchers have been able to identify that the amygdala is where fear responses occur in the brain. There are two pathways leading to and from the amygdala: one is a direct route from the frightening stimulus to the amygdala, taking only a few thousandths of a second, while the other, slower pathway travels through the higher cortex before reaching the amygdala. According to researchers, the shorter pathway, though faster, is imprecise. It is the brain’s early warning system that leads to the physical symptoms of fear and anxiety- such as increased heartbeat and sweating. The second pathway can override the first, ultimately influencing conscious feelings of fear or no fear. Due to these studies, scientists believe phobias and anxiety disorders result from an anomaly between the amygdala and related areas.

Imaging techniques such as PET and MRI scans are primarily used in human studies. Research has identified that the prefrontal cortex is also involved in the regulation of fear responses. In people with phobias, there is often dysfunction in communication between the amygdala and the prefrontal cortex, leading to exaggerated or irrational fear responses and anxiety. Unfortunately, the full mechanisms of this are not yet fully understood as the complexities of the human brain continue to be a subject of ongoing research.

Several therapies exist for treating phobias, including cognitive behavioural therapy (CBT). It is a structured therapy that aims to change patterns of thinking and behaviour that contribute to phobic reactions. One specific type of CBT used for phobias is called exposure therapy, which involves gradual and systematic exposure to the feared object or situation in a safe and controlled environment. CBT starts with less anxiety-provoking scenarios and progresses to more challenging ones. Through repeated exposure, the individual learns that the feared stimulus is not as threatening as perceived, leading to a reduction in anxiety over time. Studies report that over time repeated exposure to the phobic stimulus can lead to a decrease in amygdala activity and an increase in activity in the prefrontal cortex.A newer approach is virtual reality therapy, which uses immersive technology to simulate exposure to stimuli in a controlled environment, allowing individuals to confront their fears in a safe, controlled setting. For more extreme cases, medication may be prescribed to help manage symptoms of phobias such as anxiety and depression.