Introduction

Temporal lobe seizures are electrical disturbances¹ which originate in the temporal lobe of the brain, a region responsible for emotional processing, relaying of sensory input, and memory consolidation and retrieval. These seizures present a wide range of symptoms, such as hallucinations, uncontrolled movements, and impaired awareness.² While some individuals experience certain warning signs, others may have seizures without prior indication.

Understanding the origin, manifestation and clinical features of seizure triggers is crucial to manage Temporal Lobe Epilepsy (TLE) effectively. Triggers for seizures can be highly individualised, characterised by stress, sleep deprivation, hormonal fluctuations, the presence of certain sensory stimuli, or even dietary factors.³

This outline aims to explore factors that contribute to triggering temporal lobe seizures and to discuss certain strategies that minimise exposure and help manage symptoms. In doing so, individuals are more equipped to take proactive steps towards identifying and mitigating risk factors to improve overall well-being.

Common triggers of temporal lobe seizures

Sleep-related triggers

Sleep-related disturbances or triggers are some of the most prevalent triggers for temporal lobe seizures; proper rest is essential to regulate neuronal activity and maintain stability. Sleep deprivation results in increased neuronal excitability, making seizures more likely. Individuals with TLE have often reported heightened seizure activity following inadequate sleep.⁴

Similarly, irregular sleep patterns caused by frequent travel, staying up late, inconsistent schedules or shift work also disrupt the body’s natural circadian rhythm. These changes can lower seizure thresholds, making the brain more susceptible to abnormal electrical surges.⁵

Additionally, poor sleep quality, even with adequate hours of sleep, can contribute to seizure episodes. Conditions such as Obstructive Sleep Apnoea (OSA), night time wake (Insomnia), and restless sleep prevent the brain from reaching the deep and restorative stages of sleep.⁶ Without quality sleep, the brain struggles to regulate electrical activity, increasing seizure risk and lowering seizure control.

Stress and emotional factors

Emotional and psychological stressors also constitute as triggers for seizures, albeit less explored. The brain’s response to stress greatly influences neuronal excitability, and high levels of stress arising from environmental or psychological stressors such as work and relationships lead to the production of hormones such as cortisol and adrenaline. When released in excess, these elevated levels contribute to the overstimulation of neural activity, increasing seizure susceptibility.^7,8

Additionally, conditions such as anxiety, depression and stress arising from the occurrence of seizures creates a feedback loop, causing further seizure activity. Emotional trauma arising from childhood experiences and occurrences of Post Traumatic Stress Disorder (PTSD) have long-term neurological effects. As the brain encodes features of specific events, such as memories, sounds, and environments, the resurgence of such memories may lead to responses such as seizures. As the temporal lobe plays a crucial role in emotional processing, individuals with epilepsy may be more sensitive and vulnerable to emotional stressors, causing higher frequency or severity of seizures.

Sensory stimulation

Sensory stimulation is another common and predominant trigger for temporal lobe seizures; The temporal lobe plays a crucial role in the processing of sensory information, making individuals with TLE more susceptible to external stimuli. For instance, one of the most well-known external sensory triggers are bright and flashing lights, a hallmark trigger for individuals with photosensitive epilepsy.¹⁰ Strobe lights and rapidly changing screen scenes can overstimulate neurons, causing abnormal electrical activity.

Other sensory triggers include sudden and loud sounds, where repetitive high-pitched sounds such as sirens, alarms and loud music may startle the individual, contribute to sensory overload and increase the likelihood of seizures.¹¹ Individuals take certain precautions to manage against sensory triggers, such as avoiding environments with flashing lights or using noise-cancelling headphones in loud outdoor settings.

Dietary and nutritional triggers

Diet and nutrition play a crucial role in increasing the likelihood of temporal lobe seizures. The brain relies on a steady supply of glucose for energy, and low blood sugar (hypoglycaemia) leads to increased neuronal excitability and seizure likelihood.¹² Other instances causing a rapid spike and crash in blood sugar levels, such as prolonged fasting or consuming high-sugar foods, increase seizure risk.¹³

Another common trigger is caffeine and other stimulants, commonly consumed and found in coffee, energy drinks and medications. These stimulants increase the excitability of neurons, lowering seizure thresholds by interfering with sleep patterns and increase stress hormone levels.¹⁴

Alcohol and drug use also impact seizure activity by disrupting neurotransmitter balance, leading to withdrawal-induced seizures, even in individuals without epilepsy. Binge and heavy drinking, use of recreational drugs, such as such as cocaine, amphetamines, and cannabis, as well as nicotine or pre-workout supplements, can trigger seizure activity.^15,16

Although not common, food additives such as monosodium glutamate (MSG), artificial sweeteners, and preservatives have been reported to be potential seizure triggers. Aspartame, a common artificial sweetener, has been linked to neurological effects in some people, and MSG may cause overstimulation in sensitive individuals.¹⁷ 

Hormonal changes

Another well-documented trigger for seizures is hormonal fluctuations, and these can have a significant impact on seizure activity. Individuals, who are extremely sensitive to hormonal levels, maybe at risk for seizure activity when they experience shifts in oestrogen, progesterone, thyroid hormones etc.¹⁸ Catamenial epilepsy refers to a condition where frequent seizures are experienced during certain phases of the menstrual cycle, where oestrogen has excitatory effects on the brain, and progesterone has anticonvulsant properties.19 When the levels of oestrogen rise or progesterone drop, seizure activity may increase.

Pregnancy-related hormonal changes also influence seizure patterns, but individual differences are noted. For some, they may experience fewer seizures, but for others, it may increase due to changes in hormone levels, stress, or medication absorption. Adjusting antiepileptic medications to ensure foetal safety can sometimes make seizure management more challenging in clinical settings.²⁰

Conditions such as hypothyroidism (low thyroid levels) or hyperthyroidism (high thyroid levels) arising from thyroid imbalances contribute to seizure susceptibility. Thyroid hormone helps regulate metabolism and brain function; however, hypothyroidism can slow brain activity, reducing seizure resistance whilst hyperthyroidism can overstimulate the nervous system, increasing seizure risk.²¹ 

Medication and drug-related triggers

A crucial determinant of seizure activity is disruptions in medication use. For instance, a common trigger is missed doses of anti-seizure medication. While the body becomes continually reliant on medication, an irregular dosage may lead to a sudden abnormality in electrical activity, increasing the risk of seizures.²²

Seizure activity is also experienced when people begin to withdraw from substances or medications, such as alcohol, benzodiazepines and sedative drugs. Moreover, interaction with other drugs and medications such as antibiotics, antidepressants, antihistamines, and pain relievers may lower seizure control and interfere with drug metabolism.²³

Underlying health conditions

Lastly, a major cause of concern pertaining to seizure likelihood is the presence of underlying health conditions that may disrupt normal brain function. For instance, fevers and infections cause inflammation and alter neural activity.²⁴ Febrile seizures occurring in response to fevers are very prevalent in children, and risk from infections such as meningitis, encephalitis or severe flus may increase seizure risk by causing metabolic imbalances (low sodium, low calcium and severe dehydration).²⁵ Moreover, conditions such as diabetes and kidney disease may lead to electrolyte imbalances, making care for epilepsy trickier.²⁶

Previous trauma sustained from brain injuries can also contribute to seizure activity, where head injuries, concussions and stroke may lead to long-term changes in brain structure and function, causing conditions such as post-traumatic epilepsy (PTE) to develop years after injury.²⁷

 Managing and preventing triggers

Effective monitoring and management of seizure activity is extremely crucial to prevent temporal lobe seizures. One of the most useful tools, advised by clinicians to follow, is to maintain a seizure diary.²⁸ A seizure diary is a systematic record of seizure occurrences, potential triggers, diets, sleep patterns and emotional states, that help caregivers and clinicians recognise patterns of seizure occurrence and work towards lowering seizure risk and improving prevention.

Treatment adherence is extremely crucial to ensure seizure control, and care must be taken to ensure no medications/doses are missed, self-adjusted, or abruptly stopped.²⁹ Care must also be taken to maintain a healthy lifestyle by consuming a well-balanced diet and incorporating regular exercise.³⁰

Part of the management and assessment process also includes consideration of alternative treatments, such as ketogenic diets,³¹ particularly for those whose seizures are drug resistant. A ketogenic diet for epilepsy is a high-fat low-carbohydrate diet that aims to alter the body’s metabolism. It is particularly efficient for patients with epilepsy as it improves proper nutrient absorption and balance. By targeting mitochondrial function and GABA neurotransmitters’ activity, it helps reduce inflammation, oxidative stress and stabilises neuronal activity.

Summary

Temporal Lobe Seizures can be triggered by a multitude of factors, ranging from pre-existing health conditions to environmental disturbances and bodily processes. Due to the heterogeneous symptoms presented in epilepsy, caretakers and clinicians must personalise assessments, treatments and management for every patient. It is vital to pay close attention to factors triggering the onset of seizures, ensure lifestyle changes are being met and adhere to prescribed treatments.