Is your brain functioning differently than usual? How can you tell if it’s a mental illness or just a temporary change?
Psychiatrist Christopher M. Palmer admits that diagnosing mental illness is a complex process. It involves understanding brain function, recognizing symptoms, and considering various factors that affect mental health. Experts use different methods to identify and classify mental disorders.
Read on to explore the challenges of diagnosing mental illness and the promising new approaches that could make it easier in the future.
Diagnosing Mental Illness
Palmer writes that mental illness develops when your brain functions abnormally for an extended period, leading to symptoms that disrupt daily life and cause suffering. There are three main ways your brain might function abnormally:
- Overactivity: when a brain function happens too often or too intensely
- Underactivity: when a brain function happens less often or less intensely than it should
- Absence of function: when your brain lacks a certain function due to developmental problems while the brain was forming or cell death caused by injury or certain diseases
Palmer contends that diagnosing mental illness is complex and difficult for two reasons: Mental illnesses have no clear causes, and they have varying symptoms and risk factors.
Reason #1: No Clear Causes
Palmer explains that the first reason mental illnesses are hard to understand is that mental illnesses don’t have obvious causes like physical illnesses do. For example, we know that a virus causes the flu, but we don’t know exactly what causes someone to have depression. Because mental illnesses lack obvious causes, they’re difficult to diagnose.
One reason is that no objective tests for mental disorders exist. We can measure signs of physical diseases, like bone mass for osteoporosis, but we lack clear indicators for mental disorders. Psychiatrists instead rely on a handbook called the Diagnostic and Statistical Manual of Mental Disorders (DSM) to diagnose mental conditions, and they can only make assessments based on the symptoms their patients describe.
| The Search for Objective Tests for Mental Disorders Some experts have criticized the DSM, saying that it’s subjective and isn’t scientifically sound, but others argue that it at least provides a starting point for diagnosing something as complex as a mental disorder. While psychiatric diagnoses currently rely heavily on behavioral symptoms compared against disorders listed in the DSM, there’s ongoing research into more objective methods of identifying mental disorders. Two approaches show promise: Brain scans: In Change Your Brain, Change Your Life, psychiatrist Daniel G. Amen argues many mental health issues have physical causes in the brain that can be seen on brain scans. He explains that scans like SPECT (single photon emission computed tomography) can display the brain’s blood flow and electrical activity, allowing us to spot signs of poor brain health that typical diagnostic methods (like the DSM) miss. However, as of 2021, the American Psychiatric Association doesn’t recommend SPECT for diagnosing psychiatric conditions due to limitations of the technology. Digital tools: Digital phenotyping uses data from smartphones and wearables, such as location information, physical activity, sleep patterns, and social media activity, to monitor mental health symptoms over time. This data could serve as digital biomarkers to help detect and monitor mental health conditions, similar to how we measure bone density to diagnose osteoporosis. While these methods are still being developed, they offer hope for more accurate diagnoses in the future. |
Reason #2: Varying Symptoms and Risk Factors
According to Palmer, a second reason mental illnesses are difficult to understand and diagnose is that mental illnesses don’t manifest in the same way for everyone. There aren’t standard symptoms or risk factors across all cases—in fact, symptoms can vary dramatically among people diagnosed with the same disorder. For example, not all people exposed to trauma develop post-traumatic stress disorder (PTSD), and people who do develop PTSD may experience a wide range of symptoms.
| Obstacles to Diagnosing Complex Physical Illnesses and Mental Illnesses Just as with mental illnesses, physical illnesses can also manifest very differently from person to person. While acute illnesses (ones that resolve relatively quickly, like strep throat) have a reliable set of signs and symptoms, more complex conditions like cancer, diabetes, and autoimmune disorders, often affect multiple body systems with symptoms varying widely in both type and severity. For example, celiac disease can cause over 200 different symptoms. Many of these symptoms overlap with other conditions, and some people show no obvious symptoms at all. Thus, diagnosing and treating both mental illnesses and certain physical illnesses can be challenging. However, despite this shared challenge, people often find it harder to seek help for mental illness due to stigmas—negative attitudes and beliefs about mental illness, like shame. Many worry they might lose their job or face discrimination if others know about their mental illness. Because of this fear, more than half of people with mental health problems don’t get treatment. This stigma creates an extra barrier to diagnosis and treatment that most physical illnesses don’t face. |
Another complicating factor in diagnosing mental illness, says Palmer, is that something can be considered normal in one context and a symptom of mental illness in another. In physical illnesses, things like low bone density and high blood pressure are universally recognized as signs of a problem. But, with mental illnesses, many symptoms might be typical responses to everyday life events.
Take anxiety, for example. It’s normal to feel anxious before a test or public speaking. But, when anxiety is consistent and triggered by everyday situations, it might be a sign of a mental disorder. This difference means doctors need to consider the context of symptoms in addition to the symptoms themselves to make a diagnosis.
(Shortform note: The definition of “normal” and “abnormal” behavior has evolved over time, and some psychiatrists are concerned about the overuse of mental health diagnoses. In Saving Normal, psychiatrist Allen Frances calls this trend “diagnostic inflation.” He argues that broadening mental health categories by recognizing more behaviors as problematic may turn ordinary human experiences into medical issues. For example, the addition of prolonged grief disorder in the DSM-5 caused debate, with some arguing that it medicalizes the natural grieving process. This expanding scope of diagnoses shows the tension between two goals: identifying people who need help and avoiding unnecessary labels for normal experiences.)
| Mental Illness and Neurodivergence While Palmer defines mental illness based on whether the brain functions normally or abnormally, not all brain differences are considered illnesses. Neurodivergence is a natural variation in brain function and can include conditions like autism, ADHD, and dyslexia. While people who have mental illnesses or who are neurodivergent may face challenges, they can also have unique strengths. For example, those who are neurodivergent may have such abilities as enhanced memory, visual-spatial skills, or mathematical abilities. And mental illnesses can actually benefit leaders in times of crisis: In A First-Rate Madness, Nassir Ghaemi argues that depressive symptoms (which could be seen as underactivity in brain functions) can lead to more realistic assessments and greater empathy, while manic symptoms (overactivity in brain functions) may boost resilience and creativity. For example, Ghaemi says that Winston Churchill’s depression helped him recognize the Nazi threat early on. Churchill’s realistic outlook, a result of his depressive episodes, allowed him to understand that Hitler was a threat that couldn’t be dealt with through typical diplomacy at a time when most of England favored appeasing him. Ghaemi also suggests that Franklin D. Roosevelt’s hyperthymic (mildly manic) personality helped him guide the nation through the Great Depression. It provided him with energy and a can-do attitude, inspiring confidence in the American people during the economic crisis. |
