Information for Patients
What is neuropsychiatry?
Neuropsychiatry, in a simplified sense, is the specialized branch of medicine focusing on the assessment and treatment of changes in mood and behaviour that are experienced by persons who have a neurological condition, such as epilepsy.
A neuropsychiatrist is a medical doctor who typically completed specialist residency training in psychiatry and then went on to complete several years of further fellowship training in an accredited program focusing on the interface between neurology and psychiatry. The organization in North America which offers board certification to neuropsychiatrists is the United Council for Neurologic Subspecialties (UCNS).
How can neuropsychiatric symptoms occur in epilepsy?
Having epilepsy does not necessarily mean that you will experience significant changes in mood. However, many persons with epilepsy do report mood symptoms, such as low mood, anxiety, or irritability. If you experience this, it is helpful to understand that the mechanisms behind mood changes in persons with epilepsy can sometimes be quite different to those in persons without epilepsy. There are other potential contributors to mood that are worth considering and exploring because the treatment can be different depending on the mechanism. The different potential effects on mood in epilepsy are described in the sections below.
The discussion below is based on the NECSA Classification, which was developed within our centre in Vancouver (Hassan, I. ANZJP 2015; 49:943).
Please note that the information below is specific to epilepsy. For information on non-epileptic seizures, please click on this link to visit the ShareNES (Shared Care for Non-Epileptic Seizures) Program website.
1. Seizure effects
In simple terms, an epileptic seizure essentially involves an episode of abnormal electrical activity in the brain. Through mechanisms that are not yet fully understood, this abnormal electrical activity itself can - directly or indirectly - be associated with neuropsychiatric symptoms (changes in mood or behaviour). As shown in the diagram above, these seizure-related neuropsychiatric symptoms are classified according to their timing into:
- pre-ictal: if they occur in the lead-up to a seizure,
- ictal: if they occur during a seizure,
- post-ictal: if they occur soon after a seizure, or
- inter-ictal: if they are not closely related in time to a seizure
2. Network effects
The mechanisms described here under 'network effects' are predominantly relevant to focal epilepsy (where seizures start in one part of the brain rather than the whole brain) rather than generalized epilepsy (where seizures start in the whole brain at the same time).
The brain is responsible for many different functions, including movement, sensation, memory, language, and emotion. These functions are distributed throughout the brain such that each function is typically performed by several specific parts of the brain which connect together to form a network.
If epileptic seizures arise from one specific part of the brain, sometimes when we look at an image of the brain using MRI (magnetic resonance imaging), we can see an abnormality in brain structure in that region. This is illustrated in the diagram above. There are many different types of abnormalities in brain structure which can give rise to seizures, such as an old scar from a previous head injury or stroke, or abnormalities that are present from birth, etc. As represented in the diagram below, if this structural abnormality happens to be located within or near a network that is involved in processing emotions or behaviour, then this can result in interference with the function of this network and can cause neuropsychiatric symptoms.
3. Hormone effects
The mechanisms described here under 'hormone effects' are predominantly relevant to focal epilepsy (where seizures start in one part of the brain rather than the whole brain) rather than generalized epilepsy (where seizures start in the whole brain at the same time).
Hormones are chemical substances normally produced by certain parts of the body, including some regions of the brain. After hormones are produced, they are released into the bloodstream and carried to other parts of the body where they can a variety of biological effects. There are many different types of hormones and some can cause changes in mood and behaviour. The body normally closely controls the amount of each hormone so that the hormone's effects are not too little or too much.
When epilepsy is caused by a structural abnormality in the brain, depending on the type and location of that structural abnormality, sometimes it can produce hormones or can prevent nearby parts of the brain from producing hormones. This can cause changes in hormone levels which can lead to neuropsychiatric symptoms.
4. Side effects of treatment
Many persons with epilepsy require medication to control seizures. Each person's body chemistry is unique, and in some people, certain medications can cause changes in mood and behaviour, even though they might still be beneficial in treating epileptic seizures. Sometimes, these mood changes can improve with time as the body adjusts to a new medication. Neuropsychiatric symptoms can also occur after surgery for epilepsy and it is useful to be aware of these prior to surgery.
5. Alternative effects
Having discussed the above mechanisms, it is nevertheless important to bear in mind that changes in mood and behaviour in a person with epilepsy might not necessarily be directly related to epilepsy. Other factors that can result in neuropsychiatric symptoms can include general psychiatric conditions independent of epilepsy, psychological and social stress (apart from the stress related to living with epilepsy) and certain genetic conditions.
In summary, as explained above, there are various mechanisms by which neuropsychiatric symptoms can occur in epilepsy. It is important to distinguish between these mechanisms because each can require a different treatment approach. Furthermore, sometimes mood and behaviour symptoms can be the result of not only one but several of the above mechanisms at the same time.
The above discussion is only intended as a general overview and does not include many details in this highly specialized branch of medicine. The assessment of mood and behavioural symptoms in epilepsy is best done by a neuropsychiatrist with subspecialized training in this field.