A positive relationship between harm avoidance and brain nicotinic acetylcholine receptor availability

Opinion on monoaminergic contributions to traits and temperament

This article critically reviews evidence relating temperamental traits and personality factors to the monoamine neurotransmitters, especially dopamine and serotonin. The genetic evidence is not yet considered to be conclusive and it is argued that basic neuroscience research on the neural basis of behaviour in experimental animals should be taken more into account. While questionnaire and lexical methodology including the 'Five Factor' theory has been informative (mostly for the traits relevant to social functioning, i.e. personality), biologically oriented approaches should be employed with more objective, theoretically grounded measures of cognition and behaviour, combined with neuroimaging and psychopharmacology, where appropriate. This strategy will enable specific functions of monoamines and other neuromodulators such as acetylcholine and neuropeptides (such as orexin) to be defined with respect to their roles in modulating activity in specific neural networks-leading to a more realistic definition of their interactive roles in complex, biologically based traits (i.e. temperament).This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'.

Yoga-Based Postoperative Cardiac Rehabilitation Program for Improving Quality of Life and Stress Levels: Fifth-Year Follow-up through a Randomized Controlled Trial

Objectives:

This study was aimed to assess the efficacy of yoga-based lifestyle program (YLSP) in improving quality of life (QOL) and stress levels in patients after 5 years of coronary artery bypass graft (CABG).

Methodology:

Three hundred patients posted for elective CABG in Narayana Hrudayalaya Super Speciality Hospital, Bengaluru, were randomized into two groups: YLSP and conventional lifestyle program (CLSP), and follow-up was done for 5 years.

Intervention:

In YLSP group, all practices of integrative approach of yoga therapy such as yama, niyama, asana, pranayama, and meditation were used as an add-on to conventional cardiac rehabilitation. The control group (CLSP) continued conventional cardiac rehabilitation only.

Outcome Measures:

World Health Organization (WHO)-QOL BREF Questionnaire, Perceived Stress Scale, Positive and Negative Affect Scale (PANAS), and Hospital Anxiety and Depression Scale (HADS) were assessed before surgery and at the end of the 5^th year after CABG. As data were not normally distributed, Mann–Whitney U-test was used for between-group comparisons and Wilcoxon's signed-rank test was used for within-group comparisons.

Results:

At the end of 5 years, mental health (P = 0.05), perceived stress (P = 0.01), and negative affect (NA) (P = 0.05) have shown significant improvements. WHO-QOL BREF score has shown improvements in physical health (P = 0.046), environmental health (P = 0.04), perceived stress (P = 0.001), and NA (P = 0.02) in YLSP than CLSP. Positive affect has significantly improved in CLSP than YLSP. Other domains of WHO-QOL-BREF, PANAS, and HADS did not reveal any significant between-group differences.

Conclusion:

Addition of long-term YLSP to conventional cardiac rehabilitation brings better improvements in QOL and reduction in stress levels at the end of 5 years after CABG.

Replication of the association between CHRNA4 rs1044396 and harm avoidance in a large population-based sample

Harm avoidance is a personality trait characterized by excessive worrying and fear of uncertainty, which has repeatedly been related to anxiety disorders. Converging lines of research in rodents and humans point towards an involvement of the nicotinic cholinergic system in the modulation of anxiety. Most notably, the rs1044396 polymorphism in the CHRNA4 gene, which codes for the α4 subunit of the nicotinic acetylcholine receptor, has been linked to negative emotionality traits including harm avoidance in a recent study. Against this background, we investigated the association between harm avoidance and the rs1044396 polymorphism using data from N=1673 healthy subjects, which were collected in the context of the German multi-centre study ׳Genetics of Nicotine Dependence and Neurobiological Phenotypes׳. Homozygous carriers of the C-allele showed significantly higher levels of harm avoidance than homozygous T-allele carriers, with heterozygous subjects exhibiting intermediate scores. The effect was neither modulated by age or gender nor by smoking status. By replicating previous findings in a large population-based sample for the first time, the present study adds to the growing evidence suggesting an involvement of nicotinic cholinergic mechanism in anxiety and negative emotionality, which may pose an effective target for medical treatment.

Maternal personality traits associated with patterns of prenatal smoking and exposure: Implications for etiologic and prevention research

BACKGROUND

Little is known about the characteristics of women who smoke during pregnancy beyond demographic factors. We examined the relationship between novelty seeking, harm avoidance, and self-directedness and (a) abstinence from smoking during pregnancy and (b) average daily cigarette consumption during pregnancy.

METHODS

Participants were 826 birth mothers who made adoption placements in the Early Growth and Development Study and completed the Temperament and Character Inventory - Short Form, and interview-based smoking assessments 3-6 months postpartum. Never smokers (n=199), pregnancy abstainers (n=277), pregnancy light smokers (n=184), and pregnancy heavy smokers (n=166) were compared on personality dimensions and smoking-related processes. Using regression analyses we examined relationships between personality and (a) abstinence versus smoking during pregnancy; and (b) average daily cigarette consumption among lifetime smokers, controlling for nicotine dependence, birth father substance dependence, maternal antisocial behavior, and depressive symptoms during pregnancy.

RESULTS

Smokers with higher self-directedness and lower harm avoidance were more likely to abstain during pregnancy [O.R. 1.380; 95% C.I. (1.065-1.787); B(SE)=.322(.132); p=.015] and [O.R. .713; 95% C.I. (.543-.935); B(SE)=-.339(.138); p=.014], respectively. Novelty seeking differentiated never smokers from lifetime smokers (t=-3.487; p=.001), but was not significant in multivariate models. Lifetime smokers who abstained during pregnancy reported fewer depressive symptoms relative to never smokers.

CONCLUSIONS

Personality dimensions associated with abstinence from smoking and cigarettes per day during pregnancy may be important to consider in etiologic and intervention research.

Comparison of operant escape and reflex tests of nociceptive sensitivity

Testing of reflexes such as flexion/withdrawal or licking/guarding is well established as the standard for evaluating nociceptive sensitivity and its modulation in preclinical investigations of laboratory animals. Concerns about this approach have been dismissed for practical reasons - reflex testing requires no training of the animals; it is simple to instrument; and responses are characterized by observers as latencies or thresholds for evocation. In order to evaluate this method, the present review summarizes a series of experiments in which reflex and operant escape responding are compared in normal animals and following surgical models of neuropathic pain or pharmacological intervention for pain. Particular attention is paid to relationships between reflex and escape responding and information on the pain sensitivity of normal human subjects or patients with pain. Numerous disparities between results for reflex and operant escape measures are described, but the results of operant testing are consistent with evidence from humans. Objective reasons are given for experimenters to choose between these and other methods of evaluating the nociceptive sensitivity of laboratory animals.

Nicotine-Cadmium Interaction Alters Exploratory Motor Function and Increased Anxiety in Adult Male Mice

In this study we evaluated the time dependence in cadmium-nicotine interaction and its effect on motor function, anxiety linked behavioural changes, serum electrolytes, and weight after acute and chronic treatment in adult male mice. Animals were separated randomly into four groups of n = 6 animals each. Treatment was done with nicotine, cadmium, or nicotine-cadmium for 21 days. A fourth group received normal saline for the same duration (control). Average weight was determined at 7-day interval for the acute (D1-D7) and chronic (D7-D21) treatment phases. Similarly, the behavioural tests for exploratory motor function (open field test) and anxiety were evaluated. Serum electrolytes were measured after the chronic phase. Nicotine, cadmium, and nicotine-cadmium treatments caused no significant change in body weight after the acute phase while cadmium-nicotine and cadmium caused a decline in weight after the chronic phase. This suggests the role of cadmium in the weight loss observed in tobacco smoke users. Both nicotine and cadmium raised serum Ca²⁺ concentration and had no significant effect on K⁺ ion when compared with the control. In addition, nicotine-cadmium treatment increased bioaccumulation of Cd²⁺ in the serum which corresponded to a decrease in body weight, motor function, and an increase in anxiety.