Neurobiology and clinical implications of lucid dreaming

Several lines of evidence converge to the idea that rapid eye movement sleep (REMS) is a good model to foster our understanding of psychosis. Both REMS and psychosis course with internally generated perceptions and lack of rational judgment, which is attributed to a hyperlimbic activity along with hypofrontality. Interestingly, some individuals can become aware of dreaming during REMS, a particular experience known as lucid dreaming (LD), whose neurobiological basis is still controversial. Since the frontal lobe plays a role in self-consciousness, working memory and attention, here we hypothesize that LD is associated with increased frontal activity during REMS. A possible way to test this hypothesis is to check whether transcranial magnetic or electric stimulation of the frontal region during REMS triggers LD. We further suggest that psychosis and LD are opposite phenomena: LD as a physiological awakening while dreaming due to frontal activity, and psychosis as a pathological intrusion of dream features during wake state due to hypofrontality. We further suggest that LD research may have three main clinical implications. First, LD could be important to the study of consciousness, including its pathologies and other altered states. Second, LD could be used as a therapy for recurrent nightmares, a common symptom of depression and post-traumatic stress disorder. Finally, LD may allow for motor imagery during dreaming with possible improvement of physical rehabilitation. In all, we believe that LD research may clarify multiple aspects of brain functioning in its physiological, altered and pathological states.

Neurobiology and clinical implications of lucid dreaming

Several lines of evidence converge to the idea that rapid eye movement sleep (REMS) is a good model to foster our understanding of psychosis. Both REMS and psychosis course with internally generated perceptions and lack of rational judgment, which is attributed to a hyperlimbic activity along with hypofrontality. Interestingly, some individuals can become aware of dreaming during REMS, a particular experience known as lucid dreaming (LD), whose neurobiological basis is still controversial. Since the frontal lobe plays a role in self-consciousness, working memory and attention, here we hypothesize that LD is associated with increased frontal activity during REMS. A possible way to test this hypothesis is to check whether transcranial magnetic or electric stimulation of the frontal region during REMS triggers LD. We further suggest that psychosis and LD are opposite phenomena: LD as a physiological awakening while dreaming due to frontal activity, and psychosis as a pathological intrusion of dream features during wake state due to hypofrontality. We further suggest that LD research may have three main clinical implications. First, LD could be important to the study of consciousness, including its pathologies and other altered states. Second, LD could be used as a therapy for recurrent nightmares, a common symptom of depression and post-traumatic stress disorder. Finally, LD may allow for motor imagery during dreaming with possible improvement of physical rehabilitation. In all, we believe that LD research may clarify multiple aspects of brain functioning in its physiological, altered and pathological states.

Características psicológicas do paciente obeso grave e suas implicações pós-operatórias na cirurgia bariátrica

Obesity is a chronic disease that has multi-factorial aetiology, characterized by high degree of body fat; the degree of obesity will vary according to the Body Mass Index (BMI=m2 /kg). The severe degree of obesity is characterized by BMI>40 and it is regularly associated to endocrine-metabolic or mechanic clinical alterations, and to psychological disorders. Binge Eating (BE) results were overly high for this population. The Bariatric Surgery has been the treatment chosen by those diagnosed with severe obesity as this intervention provides prompt outcomes for loss of weight and clinical improvement conditions. However, recent research has acquiesced that after two years between 20% and 30% of people subject to this intervention gained weight. The main objective of this research is to assess the psychological and behavioral characteristics of those diagnosed with severe obesity that have been subject to Gastric Bypass Surgery in the past 24 months. Specific aspects were investigated: (1) characteristics of different personalities and diagnose of clinic and personality disorders; (2) BE and its relation with loss of weight; (2) the difference between the groups regarding post-surgery care, e.g. physical activity, psychological and dietician input. Method: 40 adults (women and men) aged 23 and 60 year-old who went through a bariatric surgery in the past 24 months, in the city of Natal-RN (Brazil); they were assembled in two groups n=20, Gain group displaying loss of < 50% of their initial surplus of weight, and the Loss group displaying loss of >50%. The research protocol is made of a socio-demographic questionnaire and 3 psychometric instruments: Rorschach – Comprehensive System; Millon Personality Inventory (MCMI-III); and the Binge Eating Scale (Escala de Compulsão Alimentar Periódica (ECAP). Through Rorschach significant differences between these groups were verified according to the kind of personality (EB) - more EB Extratensivo in Gain group and Intratensivo in Loss group – and the lack of control to express affect, increasing the answer for Color Pure at Group I. Concerning the people standardization, the sample as a whole tends to show psychic pain, denigrated selfperception, high levels of self-criticism, distorted perceptions, vulnerability to develop mood disorders and high scores regarding Suicide. MCMI-III results showed more clinic and personality disorders in Group I: Depressive Disorder and Schizotypal, Anxiety, Dysthymia, Major Depressive Disorder; Thought Disorder, Bipolar- Manic and Posttraumatic Stress Disorder. In relation to ECAP, the results indicated significant differences, showing increased BE results in Gain group. There were found significant differences between BE severity and the presence of clinic and personality disorders. Concerning the post-surgery care, the observed differences are statistically significant regarding physical activities with median-increased differences in Loss group. There is a difference between the initial weight and the time post-surgery, indicating that the higher the initial weight and the time after the surgery the higher the re-gain of weight post-surgery. Finally, the results show that the participants with more than 3 years of surgery will have Clinic and Major Depressive Disorders; Somatoform Disorder; Dysthymia. These results confirm prior studies related to BE post-surgery and re-gain of weight as well as the proneness of clinic disorders in severe obesity people. That means the results reinforce that the surgery process is a facet of the severe obesity treatment. The post-surgery process needs to be the main focus of attention and have a long-term input to sustain the care of the surgery results and the quality of life of the patients.

Antidepressivos modificam a extinção de uma memória aversiva em ratas

Treatment of major depression, posttraumatic stress disorder and other psychopathologies with antidepressants can be associated with improvement of the cognitive deficits related to these disorders. Although the mechanisms of these effects are not completely elucidated, alterations in extinction of aversive memories are believed to be present in these psychopathologies. Moreover, researches with laboratory animals usually focus on male subjects, and we have recently verified that extinction of an aversive task is reduced in female rats when compared to males. In the present study, female rats were long-term treated with clinically used antidepressants (fluoxetine, nortriptyline or mirtazapine) and tested in the plus-maze discriminative avoidance and forced swimming tests in order to evaluate learning, memory, extinction, anxiety and depression-related behaviors. All groups learned the task, but learning was somewhat faster in nortriptyline and mirtazapine-treated animals . Task retrieval was also showed by all experimental groups. Chronic treatment with fluoxetine, but not with the other antidepressants, increased extinction of the discriminative task. In the forced swimming test, animals treated with fluoxetine and mirtazapine showed decreased immobility duration. In conclusion, antidepressants interfere with learning and female rats treated with fluoxetine presented increased extinction of the aversive memory task. On the other hand, both fluoxetine and mirtazapine were effective in the forced swimming test, suggesting dissociation between the antidepressant effects and the extinction of aversive memories