We’ve been reading Brain On Fire, by Susannah Cahalan, in which she tells of her experiences with an illness that nearly killed her. Out of the many symptoms that Susannah described the one that caught my interest was her hallucinations. Normally when I hear of someone hallucinating I assume that they saw something that wasn’t actually there. In Susannah’s case her hallucinations were more than just seeing something that wasn’t there as she also “heard” people talking when no one was or she heard them say things that they did not actually say. This made me wonder just how many types of hallucinations are known. I found that there are four main types of hallucinations.

There are visual hallucinations where people see things that are not present or they see things that do not match up with reality. For example Susannah’s hallucinations led her to believe that her father was changing into different people. There are many causes of visual hallucinations including disorders as common as migraines.

Another type of hallucinations are auditory ones. Auditory hallucinations can range from hearing voices when no one is there to hearing music playing when the room is silent. They can be caused by disorders like schizophrenia or actually physical injuries like brain lesions. The man whose experiences were used to make the move A Beautiful Mind experienced mainly auditory hallucinations.

Olfactory hallucinations are known as phantosmia and this is when someone will smell something that isn’t there. Most commonly people with phantosmia will smell things like smoke, vomit, or urine but other smells can include rotting flesh or flowers. This type of hallucination is known to be caused by things like brain tumors and epilepsy.

The fourth main type of hallucinations are tactile hallucinations. This is where a person feels like something or someone is touching them. For example someone with tactile hallucinations might feel like there are insects crawling all over them. This type of hallucinations are commonly experienced by people who abuse chemical substances like cocaine.


Krucik, George. “There Are 15 Possible Causes of Hallucinations.” Hallucinations: Types, Causes & Diagnosis. Healthline Networks, n.d. Web. Feb. 2014.

“Hallucination Types.” Hallucination Types. News-Medical.net, n.d. Web. 12 Feb. 2014.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s