Sleep paralysis: Psychodynamics

Summary A patient with sleep paralysis is discussed in view of the paucity of such reports in current American literature. It is believed, however, that this disability is more common than realized and reported heretofore. This case is of additional interest in view of the still less frequent presentation of patients with sleep paralysis in the absence of narcolepsy or cataplexy. A study of this case permits conjectures as to the underlying psychodynamics in symptom-formation and as to the possible role of psychological conflict over the expression, or repression, of unconsicious homosexual drives. The symptom of sleep paralysis may then represent an, as yet, unsatisfactory compromise in view of the marked concurrent subjective anxiety often associated with it.     

Sleep study of progressive supranuclear paralysis

From a group of 9 patients suffering from progressive supranuclear palsy 11 polygraphic records and 6 tests with probenecid have been made. The changes in sleep can be correlated with the severity of the clinical picture and the stage of evolution of the disease. They support the hypothesis of a systematic progression of the lesions in the hypnogenic structures of the brain stem.     

Sleep paralysis in African Americans with panic disorder

Studies have reported a wide range in lifetime prevalence of sleep paralysis (SP). This variation may stem from cultural factors, stressful life events and genetic differences in studied populations. We found that recurrent SP was more common among African-American participants, especially those with panic disorder. Recurrent SP was reported by 59% of African Americans with panic disorder, 7% of whites with panic disorder, 23% of African-American community volunteers and 6% of white community volunteers. Significantly more early life stressors were reported by African Americans than whites. Higher levels of psychosocial stressors, including poverty, racism and acculturation, may contribute to the higher rates of SP experienced by African Americans.     

Sleep paralysis, sexual abuse, and space alien abduction

Sleep paralysis accompanied by hypnopompic ('upon awakening') hallucinations is an often-frightening manifestation of discordance between the cognitive/perceptual and motor aspects of rapid eye movement (REM) sleep. Awakening sleepers become aware of an inability to move, and sometimes experience intrusion of dream mentation into waking consciousness (e.g. seeing intruders in the bedroom). In this article, we summarize two studies. In the first study, we assessed 10 individuals who reported abduction by space aliens and whose claims were linked to apparent episodes of sleep paralysis during which hypnopompic hallucinations were interpreted as alien beings. In the second study, adults reporting repressed, recovered, or continuous memories of childhood sexual abuse more often reported sleep paralysis than did a control group. Among the 31 reporting sleep paralysis, only one person linked it to abuse memories. This person was among the six recovered memory participants who reported sleep paralysis (i.e. 17% rate of interpreting it as abuse-related). People rely on personally plausible cultural narratives to interpret these otherwise baffling sleep paralysis episodes.     

Sleep paralysis among Cambodian refugees: association with PTSD diagnosis and severity

Among Cambodian refugees attending a psychiatric clinic (n=100), 49% (49/100) had at least one episode of sleep paralysis (SP) in the previous 12 months. The annual and monthly SP prevalences were much higher in posttraumatic stress disorder (PTSD) than in non-PTSD patients. Among the PTSD patients, 65% (30/46) had monthly episodes of SP versus 14.85% (8/54) among non-PTSD patients (chi2[2, n=100]=26.78, P<.001). Moreover, patients with SP in the last month (n=30) versus those without SP had much higher PTSD severity scores. In the entire sample (n=100), the PTSD severity scores correlated significantly with the rate of SP in the last month. During SP, Cambodian refugees usually hallucinated an approaching figure (90%, 44/49). The rate of SP-associated and post-SP panic attacks was high, indicating the great distress caused by the phenomenon. SP seems to be a core aspect of the Cambodian refugee's response to trauma. When treating Cambodian refugees, and traumatized refugees in general, clinicians should assess for its presence.     

Comparative study of thyrotoxic periodic paralysis from idiopathic hypokalemic periodic paralysis: An experience from India

Objective:

There is paucity of reports on thyrotoxic periodic paralysis (TPP) from India. We report the patients with TPP and compare them with idiopathic hypokalemic periodic paralysis (IHPP).

Materials and Methods:

Patients with hypokalemic periodic paralysis (HPP) treated during the past 11 years were evaluated retrospectively. Their demographic parameters, family history, clinical features, precipitating factors, severity of weakness, laboratory parameters and rapidity of recovery were recorded. The demographic, clinical and laboratory parameters of TPP and IHPP were compared.

Results:

During the study period, we managed 52 patients with HPP; nine (17.3%) of whom had TPP and 27 (52%) had IHPP. The demographic, precipitating factors, number of attacks and severity of limb weakness were similar between the TPP and IHPP groups, except in the IHPP group, bulbar weakness was present in four and respiratory paralysis in six, needing artificial ventilation in two patients. Serum potassium was significantly lower in TPP (2.21 ± 0.49) compared with IHPP (2.67 ± 0.59, P = 0.04). Four patients with TPP had subclinical thyrotoxicosis and two had subclinical hyperthyroidism. Rebound hyperkalemia occurred in both TPP and IHPP (three versus eight patients). The recovery was faster in IHPP (26.7 ± 15.4 h) compared with TPP (34.0 ± 14.0 h), but was statistically insignificant.

Conclusion:

TPP constitutes 17.3% of HPP, and absence of clinical features of thyrotoxicosis and subclinical hyperthyroidism in TPP is not uncommon. Clinical features, demographic profile and rebound hyperkalemia are similar in both TPP and IHPP. The serum potassium level is significantly low in the TPP compared with the IHPP group.     

Sleep paralysis and recovered memories of childhood sexual abuse: A reply to Pendergrast

Pendergrast [Pendergrast, M. (in press). Sleep paralysis and recovered memories of sexual abuse: comment on McNally and Clancy. Journal of Anxiety Disorders.] provides a critique of our study on sleep paralysis among adults reporting either repressed, recovered, or continuous memories of childhood sexual abuse [McNally, R. J., & Clancy, S. A. (2005a). Sleep paralysis, sexual abuse, and space alien abduction. Transcultural Psychiatry, 42, 113–122]. We address his concerns in this reply.