One of my first encounters with patients that had voices in their head was as a young audiologist running subjects in a biofeedback study. 

At the time, we were looking at the therapeutical benefits of biofeedback for tinnitus patients. One of our perspective subjects, a 92 year old woman, reported that her tinnitus was hearing voices. Of course, with the knowledge of the time, this seemed a bit strange but we initially entered her in the study as a subject. After further interview, we found out that the voice she was hearing was her husband calling her from the kitchen, asking if “breakfast was ready”. 

While this issue alone seemed to stretch the purpose of the study, when we found out that her husband had been dead for 10 years or so, we disqualified her from our study as an inappropriate subject. Later, I learned that these patients might be suffering from a disorder now known as auditory hallucinations that could be caused by myriad of issues.  

Paracusia or auditory hallucinations is defined as the perception of sounds without auditory stimulus. According to Blom (2015), auditory hallucinations constitute a phenomenologically rich group of endogenously mediated percepts which are associated with psychiatric, neurologic, otologic, and other medical conditions, but are also experienced by 10–15% of all healthy individuals in the general population. The group of phenomena is probably best known for its verbal auditory subtype, but it also includes musical hallucinations, echo of reading, exploding-head syndrome, and many other types. The subgroup of verbal auditory hallucinations has been studied extensively with the aid of neuroimaging techniques, and from those studies emerges an outline of a functional as well as a structural network of widely distributed brain areas involved in their mediation. 

Sheikh (2017) offers that healthy people experience hallucinations as drugs, sleep deprivation and migraines can often trigger the illusion of sounds or sights that are not there. Even in the absence of these predisposing factors, approximately one in 20 people hear voices or see visual hallucinations at least once in their lifetimes, according to mental health surveys conducted by the World Health Organization. Normally, when the brain receives sensory information, such as sound, it actively works to fill in information to make sense of what it hears—its location, volume and other details. “The brain is a predictive machine,” explains Anissa Abi-Dargham, a psychiatrist at Stony Brook University School of Medicine, who was not involved in the new work. “It is constantly scanning the environment and relying on previous knowledge to fill in the gaps [in] what we perceive.” Because our expectations are usually accurate, the system generally works well. For example, we are able to hear the sound of running water or the murmur of a friend talking across the room and then react in an instant, Abi-Dargham says.  One theory posits hallucinations arise when the brain relies too strongly on these expectations, filling in details even when an actual auditory input does not exist. Culture and religion may also play a role in interpreting what individuals perceive, and whether the voices they hear are helpful or disruptive. 

Why It Can Happen

While Mental illness is one of the more common causes, there are a lot of other reasons for auditory hallucinations.  Web MD  (2018) describes 11 different situations where auditory hallucinations might occur: 

1. Alcohol and Illegal Drugs. Heavy drinking and certain street drugs, like ecstasy and LSD, more often cause you to see things that aren’t there. But they can make you hear things, too, both as you use them and when you quit after you’ve used them a long time.

2. Alzheimer’s Disease and Other Types of Dementia. It’s the later stages of Alzheimer’s when people are more likely to hear things. A similar condition called Lewy body dementia can cause it, as well (but it’s more common for them to see things — visual hallucinations — than hear things with this type of dementia.)  For some people, the voices seem so real, they talk back to them. 

3. High Fevers and Infections. High Fevers and some infections, such as encephalitis and meningitis, cause auditory hallucinations, along with the other symptoms. 

4. Intense Stress. Serious stress, as might occur after going through something traumatic, can cause hallucinations. It’s especially common to hear the voice of a loved one after their recent death.

5. Mental illness. Hearing voices is very common with schizophrenia. The voices may come from inside the head or outside, like from the TV.  These voices often argue with the person, tell them what to do, or just describe what’s happening.  It can sometimes happen with other mental illnesses as well, including:

• Bipolar disorder
• Borderline personality disorder
• Major depressive disorder
• Posttraumatic stress disorder (PTSD)
• Schizoaffective disorder

6. Migraines. Often, if you get migraines with auras, you see things. But some people hear things instead. Usually, it’s voices. And that may be more likely if you also have depression.

7. Parkinson’s Disease. It’s more likely that a patient would have visual hallucinations  with Parkinson’s, but in some cases, these patients hear things from the scenes they are seeing.

8. Side Effects of Medicine. If patients begin to hear things once they start a new medicine or their physician puts them on a higher dose of something already taken, that change could be the reason for auditory hallucinations. This concern most often affects older adults as they take more medications than those that re younger, and the possibility of these auditory hallucinations get more likely the more medicines you take.

9. Sleep issues. It is rather common to hear a sound just as you fall asleep or wake up but it is usually not an issue for a physician consultation.  If patients fall asleep randomly (narcolepsy) or have a hard time falling asleep (insomnia), auditory hallucinations are more likely.

10. Thyroid disease. Myxedema is a rare condition where the thyroid is not making enough hormone and your these levels get dangerously low. It’s a life-threatening condition that can also make cause auditory hallucinations.  

11. Tinnitus. Physicians do not think of typical ringing or hissing tinnitus as a hallucination, however tinnitus can raise the risk for auditory hallucinations.   It may be more likely if the tinnitus is combined with depression.

 When establishing the cause, it is usually the patient’s history that rules out many of these factors and allows the physician to focus on one or two of the issues for a possible cure.  When investigating these symptoms, discussions of new medications or increases in dosage, comorbid diseases, alcohol and drug use, stress and other important historical factors can shed light on the reason for these auditory hallucinations.  Whatever the reason for my research subject’s voices in our study so many years ago, it was the right thing to do to discontinue her participation and refer her to a physician to diagnose and treat her problems. 

References:

Blom, J. (2015). The Human Auditory System.  In KH Levin and P Chauvel,  The Handbook of Clinical Neurology, Elsevier, Retrieved August 13, 2018.

McGrath, J., Saha,S., Ali, A., (2015).   Psychotic Experiences in the General Population: A Cross-National Analysis Based on 31 261 Respondents From 18 Countries.  JAMA Psychiatry, Retrieved August 13, 2018.

Sheikh, K., (2017). Do You Hear What I Hear?:  Auditory Hallucinations Yield Clues to Perception. Scientific American, Retrieved August, 13 2018.

WebMD (2018).  Why Am I Hearing Things That Aren’t Real? , Mental Health, Reviewed by Joseph Goldberg, MD;  Retrieved August 13, 2018