Sleep, dreams, and memory consolidation: the role of the stress hormone cortisol. (33/147)

We discuss the relationship between sleep, dreams, and memory, proposing that the content of dreams reflects aspects of memory consolidation taking place during the different stages of sleep. Although we acknowledge the likely involvement of various neuromodulators in these phenomena, we focus on the hormone cortisol, which is known to exert influence on many of the brain systems involved in memory. The concentration of cortisol escalates over the course of the night's sleep, in ways that we propose can help explain the changing nature of dreams across the sleep cycle.  (+info)

Patients' recollections of experiences in the intensive care unit may affect their quality of life. (34/147)

INTRODUCTION: We wished to obtain the experiences felt by patients during their ICU stay using an original questionnaire and to correlate the memories of those experiences with health-related quality of life (HR-QOL). METHODS: We conducted a prospective study in 10 Portuguese intensive care units (ICUs). Six months after ICU discharge, an original questionnaire on experiences of patients during their ICU stay, the recollection questionnaire, was delivered. HR-QOL was evaluated simultaneously, with the EQ-5D questionnaire. Between 1 September 2002 and 31 March 2003 1433 adult patients were admitted. ICU and hospital mortalities were 21% and 28%, respectively. Six months after ICU discharge, 464 patients completed the recollection questionnaire. RESULTS: Thirty-eight percent of the patients stated they did not remember any moment of their ICU stay. The ICU environment was described as friendly and calm by 93% of the patients. Sleep was described as being good and enough by 73%. The experiences reported as being more stressful were tracheal tube aspiration (81%), nose tube (75%), family worries (71%) and pain (64%). Of respondents, 51% experienced dreams and nightmares during their ICU stay; of these, 14% stated that those dreams and nightmares disturb their present daily life and they exhibit a worse HR-QOL. Forty-one percent of patients reported current sleep disturbances, 38% difficulties in concentrating in current daily activities and 36% difficulties in remembering recent events. More than half of the patients reported more fatigue than before the ICU stay. Multiple and linear regression analysis showed that older age, longer ICU stay, higher Simplified Acute Physiology Score II, non-scheduled surgery and multiple trauma diagnostic categories, present sleep disturbances, daily disturbances by dreams and nightmares, difficulties in concentrating and difficulties in remembering recent events were independent predictors of worse HR-QOL. Multicollinearity analysis showed that, with the exception of the correlation between admission diagnostic categories and length of ICU stay (0.47), all other correlations between the independent variables and coefficient estimates included in the regression models were weak (below 0.30). CONCLUSION: This study suggests that neuropsychological consequences of critical illness, in particular the recollection of ICU experiences, may influence subsequent HR-QOL.  (+info)

Long-term sequelae of critical illness: memories and health-related quality of life. (35/147)

Impaired health-related quality of life after critical illness has been demonstrated in a number of studies. It is not clear exactly how or why critical illness and intensive care lead to impaired health status, but understanding this association is an important step to improving long-term outcomes of the critically ill. There is growing evidence that neuro-psychological symptoms play a significant role in this impairment and that management of patients in the intensive care unit (ICU) may influence these symptoms. This commentary examines a recent study and places this study in the context of previous studies suggesting that both amnesia and persisting nightmares of the ICU experience are associated with impaired quality of life. Further research is needed if we are effectively to understand, prevent and treat the negative sequelae of critical illness.  (+info)

The helpfulness of spiritually influenced group work in developing self-awareness and self-esteem: a preliminary investigation. (36/147)

This paper discusses an exploratory study that investigated the helpfulness of spiritually influenced group work with eight adult women who shared a history of substance abuse. The overall purpose of the group was to help participants develop their self-awareness and self-esteem. The group, which was contextualized in transpersonal theory, was organized around the following themes and experiential exercises: meditation, mindfulness practice, dream work, stream of consciousness writing, the shadow self, and other arts-based processes. Grounded-theory analysis of group sessions and individual interviews with the participants found that the participants perceived the group to be helpful in developing their self-awareness and self-esteem. While the participants identified different aspects of the group as spiritual, making-meaning was one practice that was consistently described as a spiritually sensitive process. The results of this study in this emergent field are promising and suggestions are provided for future research.  (+info)

Rhinal-hippocampal connectivity determines memory formation during sleep. (37/147)

Compared with waking state attention, volition and semantic processing play a minor role during sleep. Thus, investigating declarative memory formation during sleep may allow us to isolate mnemonic core processes. The most feasible approach to memory formation during sleep is the analysis of dream memories. Lesion and imaging studies have demonstrated that encoding of declarative memories, i.e. consciously accessible events and facts, depends on operations within the rhinal cortex and the hippocampus, two substructures of the medial temporal lobe. Successful memory formation is accompanied by a transient rhinal-hippocampal interaction. Consequently, the ability to memorize dreams may be related to mediotemporal connectivity. Therefore, we recorded EEG during sleep from rhinal and hippocampal depth electrodes implanted in 12 epilepsy patients (eight women, mean age 41.1 +/- 6.4 years). They were awakened during rapid eye movement sleep (REM) and asked to recall their dream. Via coherence analyses we show that rhinal-hippocampal connectivity values are approximately twice as large for patients with good dream recall versus those patients with poor recall. This suggests that rhinal-hippocampal connectivity is a key factor in determining declarative memory formation.  (+info)

Patients' recollections of therapeutic paralysis in the intensive care unit. (38/147)

BACKGROUND: Neuromuscular blocking agents used for therapeutic purposes, such as facilitating mechanical ventilation and relieving life-threatening agitation, paralyze patients but leave them fully conscious. Aggressive sedation or analgesia is necessary to reduce awareness, relieve fear, produce comfort, decrease anxiety, induce unconsciousness, and minimize possible complications such as posttraumatic stress syndrome. Little information is available on the extent to which patients experience awareness during therapeutic paralysis. OBJECTIVES: To determine and describe the remembered experiences of critical care patients who were given neuromuscular blocking agents and sedatives and/or analgesics to facilitate mechanical ventilation, improve hemodynamic stability, and improve oxygenation. METHODS: A phenomenological approach with in-depth interviews with 11 patients was used. Data were analyzed by using the constant comparative approach. RESULTS: A total of 4 themes and 3 subthemes were identified. The first theme was back and forth between reality and the unreal, between life and death; the subtheme was having weird dreams. The second theme was loss of control; the 2 subthemes were (1) fighting or being tied down and (2) being scared. The third theme was almost dying, and the fourth theme was feeling cared for. CONCLUSIONS: Patients can remember having both negative and positive experiences during neuromuscular blockade. Steps to improve the experiences of patients receiving neuromuscular blockers include improving assessment parameters, developing and using sedation/analgesia guidelines, and investing in quality improvement programs to provide assessment of awareness during therapeutic paralysis and follow-up and referral as necessary. Ways to decrease the use of neuromuscular blockers would also be useful.  (+info)

Evaluating the awakening criterion in the definition of nightmares: how certain are people in judging whether a nightmare woke them up? (39/147)

There is debate about whether to include in the definition of nightmares a criterion that the imagery or emotions of the nightmare caused the person to wake up. This study investigates whether people believe that they can judge this cause of awakening. 42 participants recorded for 14 nights whether they had a dream, and decided for each dream whether it had or had not woken them. They then rated on a 5-point scale (where 1 = very certain and 5 = very uncertain) how certain they were in their decision of whether or not the dream woke them. Participants' mean certainty was high for decisions that the dream woke them (mean certainty = 1.60), and for very unpleasant dreams this mean certainty that the dream woke them was very high (mean certainty = 1.27). Dreams judged to have caused awakening were found to be more unpleasant than dreams judged not to have caused awakening. Although the inclusion of the awakening criterion did not increase the association of nightmare frequency with anxiety, there may be other advantages in the use of the awakening criterion.  (+info)

Insomnia in Parkinson's disease: frequency and progression over time. (40/147)

OBJECTIVES: To examine the development of nocturnal sleeping problems in patients with Parkinson's disease (PD) over an 8-year period and to study the clinical and demographic correlates of insomnia. METHODS: 231 patients were included in a population-based prevalence study in 1993, and re-examined in 1997 and 2001. At all study visits, we applied semi-structured interviews to obtain information on clinical and demographic data, as well as on nocturnal sleeping problems. Standardised rating scales of parkinsonism, depression and cognitive impairment were used. The relationship between insomnia and demographic and clinical variables was analysed using population-averaged logistic regression models for correlated data. 231 patients were included at baseline, 142 were available for re-evaluation in 1997 and 89 patients in 2001. RESULTS: Most nocturnal sleeping problems varied little in prevalence over time, whereas problems related to turning in bed and vivid dreaming or nightmares increased. Insomnia was present in 54-60% of the patients at each of the three study visits and varied considerably in individual patients over time. The presence of insomnia was closely related to disease duration, higher Montgomery-Asberg Depression Rating Scale scores and female sex. CONCLUSION: Insomnia is a highly frequent complaint in patients with PD. It fluctuates over time in individual patients, and its origin seems to be multifactorial. Physicians should be aware of the high prevalence of insomnia in patients with PD and should examine their patients for a possible coexisting depression.  (+info)