Dream recall frequency in epilepsy patients with partial and generalized seizures: a dream diary study

Rapid eye movement sleep and epilepsy: exploring interactions and therapeutic prospects

While research interest in the relationship between sleep and epilepsy is growing, it primarily centres on the effects of non-rapid eye movement (NREM) sleep in favouring seizures. Nonetheless, a noteworthy aspect is the observation that, in the lives of patients with epilepsy, REM sleep represents the moment with the least epileptic activity and the lowest probability of having a seizure. Studies demonstrate a suppressive effect of phasic REM sleep on interictal epileptiform discharges, potentially offering insights into epilepsy localisation and management. Furthermore, epilepsy impacts REM sleep, with successful treatment correlating with improved REM sleep quality. Novel therapeutic strategies aim to harness REM's anti-epileptic effects, including pharmacological approaches targeting orexinergic systems and neuromodulation techniques promoting cortical desynchronisation. These findings underscore the intricate relationship between REM sleep and epilepsy, highlighting avenues for further research and therapeutic innovation in epilepsy management.

Relationship Between Epilepsy and Dreaming: Current Knowledge, Hypotheses, and Perspectives

The interactions between epilepsy and sleep are numerous and the impact of epilepsy on cognition is well documented. Epilepsy is therefore likely to influence dreaming as one sleep-related cognitive activity. The frequency of dream recall is indeed decreased in patients with epilepsy, especially in those with primary generalized seizures. The content of dreams is also disturbed in epilepsy patients, being more negative and with more familiar settings. While several confounding factors (anti-seizure medications, depression and anxiety disorders, cognitive impairment) may partly account for these changes, some observations suggest an effect of seizures themselves on dreams. Indeed, the incorporation of seizure symptoms in dream content has been described, concomitant or not with a focal epileptic discharge during sleep, suggesting that epilepsy might directly or indirectly interfere with dreaming. These observations, together with current knowledge on dream neurophysiology and the links between epilepsy and sleep, suggest that epilepsy may impact not only wake- but also sleep-related cognition.

A prospective controlled study on the impact of anterior temporal lobectomy on dream content

OBJECTIVE

Changes of dream ability and content in patients with brain lesions have been addressed in only about 100 case reports. All of these reports lack data regarding prelesional baseline dream content. Therefore, it was the objective of this study to prospectively assess dream content before and after anterior temporal lobectomy.

METHODS

Using the Hall and Van de Castle system, 30 dreams before and 21 dreams after anterior temporal lobectomy for drug-resistant epilepsy were analyzed. Fifty-five dreams before and 60 dreams after stereoelectroencephalography served as controls.

RESULTS

After anterior temporal lobectomy, patients had significantly less physical aggression in their dreams than preoperatively (p < 0.01, Cohen's h statistic). Dream content of patients undergoing stereoelectroencephalography showed no significant changes.

CONCLUSIONS

Within the default dream network, the temporal lobe may account for aggressive dream content. Impact of general anesthesia on dream content, as a possible confounder, was ruled out.

Differential diagnoses of nocturnal fear and movement paroxysm: a case report

Recurrent nocturnal behavioural and movement paroxysms are a diagnostic challenge for the clinical pediatrician. We report on an adolescent girl who presents recurrent stereotypical nightmare-like episodes occurring during non-REM sleep stages 1-2 (N1 and N2). We discuss the differential diagnoses between epileptic and nonepileptic events and between nocturnal frontal and temporal seizures. The pathophysiological and unusual electroencephalographical features are discussed with respect to clinical features and results of interictal FDG-PET. Conclusion In case of stereotypical nightmare-like episodes in children or adolescents, an epileptic origin has to be ruled out before a parasomnia is diagnosed. In addition, a normal awake EEG or interictal sleep EEG in the diagnostic workup may not exclude an epileptic disorder. In case of nightly stereotypic motor or affective events, an epileptic disorder should be discussed.

Dream recall frequency and content in patients with temporal lobe epilepsy

PURPOSE

To evaluate morning dream recall frequency and content in patients with temporal lobe epilepsy (TLE).

METHODS

Fifty-two patients with pharmacoresistant TLE submitted to a written dream diary during five consecutive days and continuous video-electroencephalographic (video-EEG) monitoring. A matched control group of 41 healthy subjects completed the same diary at home. The number of recalled dreams (including long dreams) and nonrecalled dream mentation were collected, and the Dream Recall Rate (DRR) was calculated. Hall and Van de Castle dream content analysis was performed.

KEY FINDINGS

Greater than 70% of patients with TLE (37 of 52) recall their dreams, but DRR rate in these patients is lower than in controls (p ≤ 0.001). Dream recall does not appear to be influenced by the presence of neuropsychological deficits nor seizure frequency. In dreams descriptions, TLE patients (vs. controls) have a higher percentage of familiarity in settings and fewer dreams with at least one success.

SIGNIFICANCE

Onirical activity of patients with TLE is different from that of healthy subjects. Our results support the role of mesial and neocortical temporal structures in dream experience. The selective activation of dysfunctional mesial structures may be responsible for some of the observed variability. However, dream content changes can also mirror social and psychological comorbidities of patients with epilepsy.

Dreaming and cognition in patients with frontotemporal dysfunction

Individuals with Parkinson's disease (PD) and temporal lobe epilepsy (TLE) have hallucinations and mild cognitive dysfunction. The objective of this work was to study dreams in PD and TLE patients using a common functional model of dream production involving the limbic and paralimbic structures. Dreams were characterised in early-stage PD (19 males) and TLE patients (52) with dream diaries classified by the Hall van de Castle system and were compared with matched controls. In PD, there were significant differences between patients' dreams and those of controls: animals, physical aggression, and a befriender were more common in patients, and aggressor and bodily misfortunes were less common. The dreams of patients with frontal dysfunction showed more aggressive features. TLE patients had lower recall than PD patients and a higher proportion of dreams involving family and familiar settings, lower proportions involving success, and a higher incidence of frontal dysfunction. The dreams of PD and TLE patients share important features.

Dreaming of seizures

Could some dreams and temporal lobe seizures share an intrinsic neuronal network? At the interplay of emotion, memory, dream, and temporal lobe seizure, we report on a patient with a left dysplastic amygdala and temporal lobe epilepsy who presented with a typical seizure while dreaming. Neuronal networks subserving affective states are suggested to be involved in emotional dream, memory recall, and amygdalo-hippocampal seizures.

Dream experience during REM and NREM sleep of patients with complex partial seizures

This study examined the effectiveness of the cognitive processes underlying dreaming in patients with complex partial seizures (CPS), by assessing the frequency of recall and the structural organization of dreams reported after awakenings provoked alternately during REM and stage 2 NREM sleep on 12 cognitively unimpaired CPS-patients (six with epileptic focus in the right hemisphere and six in the left one). Each patient was recorded for three consecutive nights, respectively, for adaptation to the sleep laboratory context, for polysomnography and for dream collection. The frequency of dream recall was lower after stage 2 NREM sleep than REM sleep, regardless of the side of epileptic focus, while the length and structural organization of dreams did not significantly differ in REM and NREM sleep. However, the length of story-like dreams was influenced by global cognitive functioning during REM sleep. These findings indicate that in CPSs-patients the elaboration of dream experience is maintained in both REM and NREM sleep, while the access to information for conversion into dream contents and the consolidation of dream contents is much less effective during NREM rather than during REM sleep. Further studies may distinguish between these two possibilities and enlighten us as to whether the impaired memory functioning during NREM sleep is a side effect of anticonvulsant treatment.