Introduction

Temporal lobe epilepsy (TLE) is a neurological disorder caused by recurrent seizures in temporal lobe of the brain due to abnormal electrical activities. Despite typical physical symptoms associated with epilepsy, do you know it could also lead to emotional and behavioural changes? Individuals with TLE often experience significant emotional (affective) and behavioural changes such as mood swings, anxiety, depression, irritability, and personality changes. 

Due to the potential adverse effect on well-being and quality of life among TLE individuals, caregivers, and even healthcare providers, familiarising ourselves with its relevant emotional and behavioural changes are crucial to promoting recognition, timely diagnosis and effective management for comprehensive, holistic care and support towards the affected population and loved ones. 

Emotional changes in TLE  

Depression

Depression, also known as Major Depressive Disorder (MDD), is frequently reported among TLE, particularly between epileptic episodes (interictal).¹ Typically present as persistent sadness, hopelessness, worthlessness, and disinterest in activities. Individuals may often feel emotionally drained, associated with constant fatigue, sleep disturbances, appetite changes and a variety of pain that impairs daily functioning and interpersonal relationships. There are also higher suicidal risks or thoughts among TLE due to underlying hippocampal and amygdala lesions, stress and uncertainties experienced, plus antiseizure drug consumption.²

Anxiety

Anxiety is significantly common among TLE at different time points, causing excessive nervousness, distress, and unease adversely affecting daily life. Despite being a reaction to diagnosis or after the first seizure fearful of repetitions (pre-ictal), it can also be a TLE symptom. Often show up as aura (warning sensation), sudden déjà vu (feeling of familiarity) or jamais vu (feeling of unfamiliarity) sensations, as well as autonomic symptoms like sweating or heart palpitations, particularly prominent during (ictal, as part of aura), between (interictal) or after seizure episodes (post-ictal).^3,4,5

Fear or panic attacks

A sudden fear or panic attack, also known as ictal fear is common upon TLE. Despite being mistaken for a regular panic attack sometimes, it can be a partial seizure (aura, the seizure warning sign).⁶ Often manifesting as an unexpected, overwhelming sense of fear or impending doom, together with a dissociative sense of derealisation and physical symptoms like rapid heartbeat, dizziness, pins and needles (paresthesia), chest pain, and tremors. Aura symptoms such as unusually stronger senses and the rising sensation in the stomach before seizure can also be distinctive to a TLE diagnosis.⁷ 

Mood swings 

Mood swings or emotional lability disproportionated to situations is another prevalent humour  change upon TLE. It is typically experienced or observed before, during (as part of aura), and after a seizure, even in the absence of any seizure signs. Often shows up as rapid, intense, abrupt shifts in emotions ranging from joy, and inappropriate laughter, to sudden outbursts of anger or sadness. Amongst the population, individuals with ictal fear are also found to have the most impaired facial and fear emotion recognition ability, due to the main function of the temporal lobe in processing emotions and sensory perceptions.⁸ 

Behavioural changes in TLE 

Psychotic symptoms 

TLE can present with psychotic symptoms such as hallucinations, delusions, as well as disorganised thinking, making individuals less in touch with reality. While a unique olfactory hallucination of burning leather, or less commonly perfume and after-shave lotion has been atypically presented, less commonly auditory or visual ones.⁹ Paranoid, grandiose delusions are also other likely symptoms among those with frequent TLE long history.¹⁰

Automatisms 

Automatisms in TLE are the involuntary, repetitive movements or actions during a seizure with impaired awareness. These include lip smacking, hand rubbing, excessive picking, writing (hypergraphia) or other purposeless behaviours that mostly involve the hands and mouth.   

With less common automatism of vocalisations, ictal speech and affective behaviours without fear and other rarer “leaving behaviours” such as crying, laughing, and even running.^11,12

Agitation and aggression

Recurrent episodes with interictal agitation are rare yet well-recognized among TLE.¹³ Often show up as a feeling of restlessness or anxiety, it can also be co-occurring with aggressive behaviours, typically between or after seizures under minor stressors, due to impaired awareness, confusion and disorientation. It is also sometimes called “episodic dyscontrol" or "intermittent explosive disorder" (IED) due to forceful resistance when being restrained and its potential destructiveness. Though it is not always presented in every individual, it is found more relevant to those with early onset TLE that are refractory,  left-hemisphere dominant, as well a a history of antisocial personality disorder (ASPD).¹³

Obsessiveness and impulsivity  

Obsessiveness and impulsivity stemming from limbic system dysfunction can sometimes lead to repetitive thoughts, behaviours and emotional reactivity among TLE. Individuals may exhibit obsessive, preoccupied thoughts and compulsive behaviours like excessive focus on specific ideas, rumination of past events, even religious or philosophical preoccupation that intensifies restlessness in contributing to prolonged emotional rigidity or viscosity, resembling obsessive-compulsive disorder (OCD) or obsessive-compulsive personality disorder (OCPD). Impulsivity, showing up as an abrupt mood shift, aggressive outburst, socially inappropriate behaviour or risky decision-making can also fluctuate along with seizure activity, particularly before or after TLE.^14,15

Sexual behavioural changes

People with TLE can experience changes in sexual behaviours due to the disrupted limbic and hypothalamic pathways. While hyposexuality, as the decreased sexual interest or activity has been the most common. Increased sex drive (libido) or sexual behaviours (hypersexuality), sexual behaviour during seizures (ictal sexual behaviour), and other unusual sexual fantasies or paraphilias are also possible due to amygdala dysfunction, seizure-related hormonal changes and medication side effects.^16,17

Apathy and social withdrawal 

Apathy and social withdrawal can result from prefrontal cortex-led cognitive and memory impairments in TLE. Individuals may exhibit reduced motivation to previously enjoyed activities, emotional blunting, and diminished interest in social interactions. TLE that disrupts emotional and behavioural regulatory centres can also lead to apathy, resulting in a lack of initiative and, hence isolation. Chronic TLE that worsens these over time, can exacerbate depression, social difficulties and daily functioning impairments.^18,19,20 

Neurobiological and structural correlates 

Role of amygdala and hippocampus in emotional processing 

The amygdala and hippocampus are crucial for emotional processing. The amygdala detects and regulates emotions, particularly fear and threat responses that influence anxiety, agitation, aggression, and emotional memory. The hippocampus, critical for memory formation and learning, modulates these emotional responses to shape the way we respond to these situations. Together, helping to regulate mood, emotional learning, and socially appropriate behaviours. Hence, resulting in mood instability, agitation and dysregulated behavioural control. 

Impact of hippocampal sclerosis on mood regulation

Hippocampal sclerosis in TLE could impair the connections between the hippocampus, amygdala, and prefrontal cortex, leading to mood regulation.²¹ As the hippocampus's role in stress regulation is affected, in turn heightening emotional reactivity and reducing stress resilience, increased emotional instability, depression, anxiety and agitation are resulted. Thereby, contributing to emotional processing difficulties, apathy and social withdrawal over time. 

Neurotransmitter imbalances 

Neurotransmitter imbalances, particularly that of serotonin, dopamine, and gamma-aminobutyric acid (GABA) play a role in emotional and behavioural changes in TLE. While low serotonin is linked to depression and anxiety, disrupted dopamine signalling often results in mood swings and impulsivity. GABA deficiency that reduces inhibitory control could increase excitability, hence emotional dysregulation.²² These imbalances, exacerbated by abnormal electrical signalling in seizure activities have made TLE individuals more prone to mood, behavioural and social functioning impairments. 

Impact on quality of life 

Emotional distress and its influence on seizure control

Emotional distress upon TLE can worsen seizure control, in turn, creating a vicious cycle of stress and seizure exacerbation. While restlessness, anxiety, depression, and anger arise from unpredictable seizures can increase emotional sensitivity and reactivity, potentially lowering the seizure threshold.  Poor seizure control can also intensify emotional distress on the other way around, impacting overall well-being and quality of life. 

Social stigma and relationship difficulties

Social stigma and relationship difficulties are common among the TLE population. Individuals may face misunderstandings or judgements concerning their visible seizures or emotional and behavioural changes. This can lead to strained relationships, even social isolation and withdrawal, causing them a lack of social support that further adversely impacts their emotional well-being and confidence in social interactions. 

Occupational and functional impairment

Occupational and functional impairment has also been a challenge faced by the TLE population. While seizures and the associated cognitive and memory issues can limit work performance and hinder social interactions. Struggling with tasks that require focus, attention, or decision-making can further lead individuals to decreased productivity, social withdrawal, and challenges in employment, even daily routine maintenance. 

Management and treatment approaches 

Various treatments are available for emotional and behavioural issues among TLE:¹⁷

Medications 

There are a wide variety of anti-seizure drugs such as lamotrigine or levetiracetam that can help to balance seizure control and psychiatric side effects. Antidepressants, particularly selective serotonin reuptake inhibitors (SSRIs) and anxiolytics are used to address anxiety and depression in comorbid cases. Antipsychotics like quetiapine, or mood stabilizers such as valproate or carbamazepine are also prescribed to help stabilise mood, manage agitation and aggression, to improve emotional regulation whilst controlling seizures. 

Psychotherapy and behavioral interventions

Psychological and behavioural interventions can be used to manage the emotional and behavioural changes among TLE.

• Cognitive behavioural therapy (CBT) that identifies unhelpful thinking patterns can address anxiety, depression and impulsivity
• Mindfulness-based stress reduction (MBSR) can facilitate stress and emotional regulation
• Behavioural therapy focuses on maladaptive behaviour modifications that can improve aggression and social withdrawal 
• Support groups in the provision of peer social connections and coping strategies 
• Psychoeducation, in helping individuals with TLE, their families and caregivers understand the emotional and behavioural impacts associated with fostering better seizure management and adaptive coping  

Neuromodulation and surgery

Neuromodulatory or surgical may be considered when TLE is medication-resistant or refractory. Vagus Nerve Stimulation (VNS) can be used to manage secondary emotional and behavioural changes to TLE through electrical impulses delivered via the vagus nerve to the brain, reducing depression, anxiety and seizure symptoms. Surgeries targeting brain areas involved in seizure generation and emotional processing may be considered to eliminate the adverse effects. 

Summary

Emotional and behavioural changes are some common yet complex secondary effects of temporal lobe epilepsy. With a potential intricate interplay amongst depression, anxiety, panic, mood swings, hallucinations, delusions, automatism, aggression, impulsivity, and social withdrawal. These can significantly heighten emotional distress and social and occupational difficulties, hence overall well-being and quality of life of the affected individuals. While early recognition and holistic management by neurologists specialising in epilepsy are crucial in minimizing the possible functional impairments, multidisciplinary medical professions including psychologists, psychiatrists, and even neurosurgeons are also critical in the formulation of rehabilitation plans to maximise and improve both the psychiatric and seizure outcomes.