Approximate entropy and point correlation dimension of heart rate variability in healthy subjects

The contribution of nonlinear dynamics to heart rate variability in healthy humans was examined using surrogate data analysis. Several measures of heart rate variability were used and compared. Heart rates were recorded for three hours and original data sets of 8192 R-R intervals created. For each original data set (n=34), three surrogate data sets were made by shuffling the order of the R-R intervals while retaining their linear correlations. The difference in heart rate variability between the original and surrogate data sets reflects the amount of nonlinear structure in the original data set. Heart rate variability was analyzed by two different nonlinear methods, point correlation dimension and approximate entropy. Nonlinearity, though under 10 percent, could be detected with both types of heart rate variability measures. More importantly, not only were the correlations between these measures and the standard deviation of the R-R intervals weak, the correlation among the nonlinear measures themselves was also weak (generally less than 0.6). This suggests that in addition to standard linear measures of heart rate variability, the use of multiple nonlinear measures of heart rate variability might be useful in monitoring heart rate dynamics.     

ROD VISION AS CHROMATIC VISION

S tabell , B. Rod vision as chromatic vision. Scand. J. Psychol ., 1968, 9, 282–288.—It was found (I) that the smallest quantity of light of pre-stimula-tion which produces color upon test-stimulation, stands in unique relation to the intensity of the specific threshold, and (2) that the size of the pre-and test-stimulation fields may affect the duration of the after-image. The results are judged to indicate that pre-stimulation of cones creates the disposition for the color-related response, and that the color-related response is generated centrally to the photochemical systems of the receptors.     

COLOR THRESHOLD MEASUREMENTS IN SCOTOPIC VISION: Test-stimulation varied

S tabell , U. & S tabell , B. Color threshold measurements in scotopic vision. II. Test-stimulation varied. Scand. J. Psychol ., 1968, 9, 129–132.—The color threshold curve generally coincides with the dark adaptation curve of the rods, irrespectively of test-stimulation variation, confirming the assumption that a threshold response of rods may initiate a color-related process. Variation of color threshold intensity is thus assumed to reflect variation of rod threshold intensity.     

Mental health of outpatient pediatric patients

The purpose of this study is to estimate the percentage of mental health problems in a pediatric outpatient Norwegian clinic. We used the Strengths and Difficulties Questionnaire to screen for mental health problems. Families of children aged 4–11 took part in the study, and 380 out of 982 possible families consented to take part, and 349 families contributed with questionnaire data. The main referral reasons for the patients were asthma, eneuresis and stomach pain. Mothers reported that 17.4% of boys and 17.8% of girls displayed mental clinical problems. The prevalence of problems did not differ significantly between somatic diagnostic groups. Although the study has low participation, it underlines the necessity of screening all pediatric patients for mental health problems. Future research in pediatric clinics should include factors of psychology because pediatric problems are not caused by somatics alone.     

A comparison of coping strategies in patients with fibromyalgia,chronic neuropathic pain,and pain‐free controls

Patients suffering from chronic pain may benefit from learning adaptive coping strategies. Consensus on efficient strategies for this group of patients is, however, lacking, and previous studies have shown inconsistent results. The present study has examined coping strategies in two distinctly different groups of chronic pain patients and a group of healthy controls. Thirty neuropathic pain (NP) patients, 28 fibromyalgia (FM) patients, and 26 pain‐free healthy controls completed the Coping Strategy Questionnaire (CSQ‐48/27) and rated their daily pain. The results showed that FM and NP patients did not cope differently with pain. The only difference between the groups was that FM patients felt more in control of their pain than NP patients. Both patient groups used more maladaptive/passive coping strategies, but surprisingly also more adaptive/active coping strategies than healthy controls. However, FM patients with high levels of passive strategies felt less in control than FM patients with low levels of passive strategies. This was not seen in NP patients. An important implication for clinical practice is therefore that passive coping strategies should be restructured into active ones, especially for FM patients. Otherwise, the same psychological treatment model can be applied to both groups since they use similar coping styles.     

Coping With Strain (CWS) course – its effects on depressive symptoms: A four‐year longitudinal randomized controlled trial

The Coping With Strain (CWS) course is a modification of the Coping With Depression (CWD) course. CWD is by far the most studied psycho‐educational intervention to reduce and prevent depression, but CWD has never been tested in a randomized controlled trial in the workplace. This study seeks to examine the extent to which CWS, on a short‐term and a long‐term basis, reduces depressive symptoms in employees. After advertising at workplaces, 119 employees were randomized into Intervention Group I (IG1), which immediately participated in CWS, or Intervention Group II (IG2), which functioned as a control group for six months until its participation in CWS. The follow up period lasted for four years in both IG1 and IG2. Linear mixed models were fitted to the data. Depressive symptoms were significantly reduced during the course. The reduction of depressive symptoms was maintained over a period of four years in both IG1 and IG2, although there is a slight increase towards the end of the follow‐up period. CWS is effective in reducing depressive symptoms among employees. The effects are long lasting and may be maintained over a period of four years.     

Anxiety and Threat Perception Abnormalities in Normal Children

The current study examined the relationship between childhood anxiety and threat perception abnormalities. Children (N = 105) were exposed to stories reflecting three types of anxiety: social anxiety, separation anxiety, and generalized anxiety. From children's reactions to the stories, a number of threat perception indices were derived. Children's level of anxiety was assessed by means of questionnaires and a structured diagnostic interview. Results indicated that high levels of anxiety, as measured by questionnaires and interview, were accompanied by a high frequency of threat perception, high ratings of threat, a high frequency of threatening interpretations, high levels of negative feelings and cognitions, and an early detection of threat. Furthermore, results seemed to suggest that threat perception abnormalities were mediated by children's general level of anxiety rather than by levels of specific anxiety symptoms.     

The function of language in parent‐infant psychotherapy

Parent‐infant psychotherapy, a rather new field in psychoanalysis, raises questions of how to conceptualize the clinical process. Previous publications have used semiotic concepts to account for the therapist's non‐verbal communication and investigated the countertransference, including what the baby might grasp of its variations. The present paper focuses on another argument for using verbal interventions to a baby in therapy; they present him with a symbolic order that differs from that of the parent. The qualitative difference between the parent's and the analyst's address is conceptualized by Dolto's term parler vrai. The therapeutic leverage is not the analytic interventions' lexical content but their message that words can be used to expose conflicts. Thereby, one can transform warded‐off desires into demands that can be negotiated with one's objects. The reasons why this address catches the baby's attention are discussed. A prerequisite for such attention is that the infant brain is prewired for perceiving words as a special communicative mode. Relevant neuroscientific research is reviewed in regard to this question. The presentation relies on concepts by Dolto, Lacan and Winnicott and findings from neuroscience and developmental psychology. It also briefly discusses Chomsky's linguistic concepts in relation to these therapies.