Chronic pain can have significant effects on a patient's mood and memory. This article dives into how memory and mood are affected and the science behind it all!
Mood
Living with chronic pain can be very difficult to deal with mentally. Untreated chronic pain can feel as though it’s creeping into every area of your life, changing things in very negative ways. These changes, combined with the experience of being in persistent pain, can undoubtedly change your mood.
Fear
Many people become fearful of their pain. Acute pain acts as a warning system. It lets you know that something is wrong. So of course, when you are experiencing chronic pain, you naturally feel that something is wrong with your body. However chronic pain doesn’t mean that there is damage within your body!
Chronic pain means the pain alarm system has become faulty. It’s telling you there’s a threat, even when there isn’t one present! If you’re constantly on alert, feeling that there is a threat any time there is pain, this can be extremely worrying and frightening!
This fear can manifest as pain hypervigilance, which means that the person in pain is constantly aware of their pain. It can also turn into catastrophizing, meaning that you might always be worrying about your pain and expect pain in situations that haven’t even happened yet. For example, you might worry about how chronic pain is going to affect your future, expecting the pain to worsen and feeling that things are never going to get better.
This fear and worry can turn into fear avoidance. This means that patients are avoiding situations that they perceive might worsen their pain. This is an understandable response. When you’re already in pain, you don’t want to make it worse! However, this fear avoidance can increase your pain levels. You’re essentially feeding back to your brain that it should continue producing pain signals in reaction to the situations you’re avoiding. Lack of activity can also lead to deconditioning, meaning your muscles and body become weaker because they aren’t being used.
Avoidance of activity can lead to social withdrawal and a breakdown of vital social connections. It can also result in reduced functioning, meaning people may be unable to work or engage in the activities that used to make them happy. Of course, this can contribute to a drop in mood and quality of life.
Stress
The experience of being in pain is stressful. Yet stress can also worsen the pain. This is a vicious cycle known as the stress and pain cycle. When you’re stressed, excess cortisol (known as the stress hormone) and adrenaline are released to ready your body for the ‘fight or flight’ response. When stress is prolonged, these hormones are sent out excessively, and rather than being helpful, they can have serious negative impacts on the mind and body.
Being in a constant state of stress can make you on edge, contributing to anxiety along with the hypervigilance, catastrophizing, and fear avoidance I mentioned earlier. As with acute pain, the stress in a healthy person means that there is an outside threat. This is helpful and important for survival. However, when stress becomes chronic, just like chronic pain, it becomes unhelpful and damaging.
Stress can also contribute to low levels of serotonin and problems with how the body processes serotonin. Among other jobs in the body, serotonin is responsible for maintaining a stable mood and a sense of well-being. When its levels are affected, it can lead to problems with regulating emotions and mood.
Self-Esteem And Sense Of Self
Reduced levels of functioning can result in people with chronic pain needing to ask for help to complete day-to-day tasks. This can hurt confidence levels. There are so many difficult feelings that can come from losing your sense of independence. You can feel like a burden. You may start worrying about how your loved ones view you. You may feel that they are going to get annoyed with you because you’re constantly needing assistance. You can start to feel frustrated and annoyed with yourself because you ‘should’ be able to do these things that seem small. You can become irritable and short-tempered, both with yourself and others.
Reduced functioning can make you feel incapable and contribute to worries about the future. Loss of independence, often combined with the loss of the ability to work and engage in hobbies, can lead to feelings of a confused sense of self. Patients may start to worry about what their life will look like if the pain continues, and whether they will ever be able to reach the goals and vision for their life that they had previously. This detailed study on the impact of chronic pain on self-identity explains that “Pain that persists and continues to impose interruption and interference may be much more damaging to one’s sense of self or identity.”
Many people with chronic pain struggle to keep up with self-care, including daily hygiene. Fatigue and reduced functioning mean it’s often draining to get ready and present yourself well. Often how you look can come at the bottom of your list of priorities. This understandably can be frustrating, knocking your confidence and making you feel that you aren’t the same person you were before.
Mental Illness
Many chronic illnesses list anxiety and depression as a symptom. This is because many aspects of living with chronic pain can contribute to causing or worsening comorbid mental illnesses. The thought of being in pain for the long term can be overwhelming, especially if no adequate treatment options have been offered.
The reduced functioning, we mentioned earlier often results in a feeling of helplessness and hopelessness, both about the future and about not being able to do anything to help themselves. When you can’t do things that you used to find fun, depression often follows. The feeling of being a burden to those you love can play a big part in depression.
When humans lack social contact, it can make us feel isolated and alone, which contributes to depression. The fear of the activity we talked about can exacerbate anxiety, in turn making us avoid the activity even more. The reduced confidence and confused sense of self we discussed can understandably make an individual feel anxious and depressed. Increased stress levels have a significant impact on anxiety.
Memory
It’s not just our mood that is impacted by chronic pain. Being in chronic pain changes not only how our brains work, but the actual structure of our brains. A study into memory processing in chronic pain patients found that two-thirds of those who participated struggled with memory. On days when their pain was low, they were able to perform much more effectively in tasks, while on high pain days, participants struggled to perform. The study also concluded that “pain may disrupt the maintenance of the memory trace that is required to hold information for processing and retain it for storage in longer-term memory stores.”
Reduced Grey Matter
Chronic pain reduces the grey matter in our brains. Grey matter is the area of our brains that controls our memory, along with how we learn about the outside world, how we process information, and how we form thoughts. It also influences our attention span. This in-depth study on the loss of gray matter in pain patients found that they typically lose the same amount of gray matter that is lost within 10 to 20 years of normal aging! They also discovered that the longer you are in chronic pain, the grayer matter you lose: “The decreased volume was related to pain duration, indicating a 1.3 cm3 loss of gray matter for every year of chronic pain.”
Due to this loss of gray matter, those of us with chronic pain can struggle with memory. We can also find it difficult to focus on the task at hand as well as to think problems through and come to logical solutions.
Reorganization And Functional Changes In The Brain
Chronic pain changes the structure of our brains, affecting many of the brain’s regions. This study explains that chronic pain causes, “gross reorganization and functional changes in both cortical and subcortical structures, including the medial prefrontal cortex, thalamus, amygdala, and anterior cingulate cortex”.
The medial prefrontal cortex is involved in many processes including decision-making, personality expression, and most aptly in this case, long-term memory retrieval. The thalamus has an important role in passing on signals about what is happening in the outside environment and is pivotal in short-term memory, working memory, and spatial memory.
Working memory is short-term memory. This type of memory is what we use when we are trying to remember how to carry out a certain task. For example, if we read a recipe and then recall the steps so that we can cook the meal. Spatial memory is how we process our environment and learn from what is happening around us.
Among other functions, the amygdala helps us to process emotions and store memories about events and the emotions they evoke. We can then use the memory of that experience (and how we felt about it) in the future to make appropriate decisions about our well-being. The anterior cingulate cortex is vital in controlling our emotions. Pivotally it also helps to process information passed on by other areas of the brain about what is happening in the environment and aids in consolidating memories in accordance.
Significantly, the hippocampus is an area of the brain that is the most affected by chronic pain. Critically, this study found that “normal neurogenesis is decreased in the presence of chronic neuropathic pain.” Neurogenesis is the process within our brains that generates new neurons and integrates these new neurons into the existing pathways so that they function properly. The hippocampus is the area in our brain that turns short-term memories into long-term memories, allowing us to store our memories so that we can recall them later.
The hippocampus also helps us to process declarative (or explicit) memories. Declarative memories are those we use for facts, like what time the supermarket closes, our friend’s address, or what time our partner finishes work. This area of the brain also helps with spatial memory. Spatial memory helps us recall pathways or routes, such as the route to work or how we get to the doctor’s office.
Interestingly, this cortical reorganization differs depending on the chronic pain diagnosis as this study explains. In some chronic diagnoses (like neuropathy), it’s the severity of pain that dictates the extent to which the reorganization takes place. While in other conditions (like fibromyalgia) it’s the length of time the patient has been chronically ill which dictates the level of change within the brain.
Disrupted Equilibrium
In a healthy brain, there is an equilibrium between areas of the brain. This means that when one area of the brain is active, the others will be less active so that the active part can do its job properly. For example, if you’re trying to solve a problem or focus on one specific task, the areas of the brain not needed will be ‘quieter’.
However, in those with chronic pain, the area of the brain which controls emotions is constantly active. This means that when other parts of the brain are trying to function, that area of the brain is still ‘noisy’. This can wear down the neurons in that area of the brain and make it hard to concentrate, as this article explains. Overactivity in this area of the brain contributes to problems with memory, concentration, and thought processes. It’s also understood to worsen depression and general mood.
Fatigue And Insomnia
Chronic pain and the symptoms that come along with it can make it difficult to sleep properly. Sleep is not only important for our physical health but also for our mental and cognitive health. Sleep gives our brains the time they need to rest and recuperate so that our brains can function properly during the day. When we lack sleep, our minds can struggle to function, which can exacerbate problems with memory and concentration.
Fatigue is a common symptom of many chronic pain conditions. Fatigue is not just a feeling of tiredness, but rather of complete exhaustion both mentally and physically. Being fatigued can make it tough to function at all, never mind remembering where you’ve put something or what you were supposed to be doing.
Cognitive ‘Fog’
Some chronic pain conditions are accompanied by cognitive ‘fog’. For example, I live with fibromyalgia and experience fibrofog. The experience is similar to how it sounds, almost like thinking through a thick fog which makes it hard to focus, to remember what you were going to say or what the task at hand was. The severity of this cognitive fog can vary greatly, from mildly annoying to severely debilitating. It can also vary in one person, just as other symptoms of chronic pain. For example, when I am having a flare of symptoms or a bad pain day, my fibro fog is much worse.
Opioid Use
Many chronic pain patients have been prescribed opioids. Opioids are strong painkillers that work by attaching to receptors within the central nervous system and blocking the signals telling the brain to send out pain messages. Opioids are a controversial topic and have many side effects and risks attached. One of these risks is a decline in cognitive functioning and memory, especially in the long-term use of opioids. This study on the topic found that 73% to 81% of the cognitive problems reported in those taking opioids were memory deficits.
Opioids can also contribute to problems in sleep, which as we discussed earlier can contribute to memory issues and cognitive processing. Long-term use of opioids has been linked to depression and declines in a patient’s moods over time.
Changes In Remembering Pain
Patients who live in chronic pain have difficulty recalling their experience of pain accurately. It seems that the memories of chronic pain are stored incorrectly, leading patients to remember their experience as more severe than it was. This study on the matter explains that how differently patients recall their chronic pain from the experience is dependent on many factors including: “emotional context, an individual’s personality traits and mood, and the participants’ previous experience with pain”
Increased Risk Of Dementia
These changes in brain structure and problems with memory decline have been strongly linked to a higher probability that patients with untreated chronic pain will struggle with dementia in old age. This study focused on a large sample group of over 1000 participants and found that, “Participants with persistent pain had a mean 9.2% more rapid decline in memory score than participants without persistent pain”, and that the probability of dementia increased by 7.7%.
How can this be tackled?
All of this can sound worrying, but the majority of the effects chronic pain has on memory and mood can be reversed. This study explains that the cortical reorganization I mentioned earlier can be reversed through neuroplasticity. This means that just as the brain has learned to produce chronic pain and the according changes within the brain, it can also be retaught to regain normal functioning. Grey matter volume can also be regained.
The longer a person has been in chronic pain, the more deeply embedded these changes are. This doesn’t mean that they can’t be reversed, but it does mean that they will take longer and require more work. This simply means that the sooner you seek effective treatment and learn how to effectively manage your pain, the sooner you can get things back under control.
Mental illness can be treated with talking therapies and medication if needed. Anxiety and depression can be recovered from. Fear can be tackled and functioning regained through appropriate treatment, such as Cognitive Behavioral Therapy (CBT). Stress levels can be reduced through highly effective treatments such as mindfulness, and the stress and pain cycle can be broken!
With the right treatment, you can live well and beyond chronic pain. Even though it might not feel like it sometimes, there is hope. To help you get there, check out our app for chronic pain – download the links below.
Precision Pain Care and Rehabilitation has two convenient locations in Richmond Hill – Queens and New Hyde Park – Long Island. Call the Queens office at (718) 215-1888, or (516) 419-4480 for the Long Island office, to arrange an appointment with our Interventional Pain Management Specialist, Dr. Jeffrey Chacko.
