Low cholesterol is a risk factor for attentional impulsivity in patients with mood symptoms

This study examined the relationship between cholesterol levels and impulsivity in a large sample of patients with mood symptoms. Three hundred and one patients with mood, anxiety, and personality disorders completed a battery of psychometric scales including the Barratt Impulsiveness Scale-Version 11 (BIS-11) and the Profile of Mood States (POMS). On the same day of psychometric assessment, blood samples were analyzed for total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C). Statistical analysis controlling for the confounding effects of age, gender, diagnosis, and current mood symptoms showed that lower TC levels were associated with increased attentional impulsivity. There was a weak linear correlation between TC and attentional impulsivity across the entire range of TC levels (110-295 mg/dL) but a highly significant difference between participants with TC levels lower than 165 mg/dL and the rest of the sample. The current study adds to the growing body of evidence pointing to the association between serum cholesterol and mental health. Considering that attentional impulsivity is a demonstrated risk factor for suicide, patients presenting with low cholesterol and mood symptoms may warrant increased clinical attention and surveillance.     

Schedule-induced polydipsia in the spontaneously hypertensive rat and its relation to impulsive behaviour

Eight Spontaneously Hypertensive Rat (SHR), 8 Wistar-Kyoto (WKY) and 8 Wistar rats, all male, maintained at 80-85% of their free-feeding weight by controlled access to food, were exposed to a series of fixed time (FT) schedules whereby food pellets were regularly delivered regardless of the animals’ behaviour. The FT values used were 9, 15, 30, 60, 120 and 180 s, with the order of presentation of the schedules among the animals being counterbalanced (except under the FT 120-s and 180-s schedules, which were successively presented as the last two of the series). Due to freely available access to water, the animals developed schedule-induced drinking under all FT schedules, marked by the characteristic bitonic function that relates the number of licks and amount of water drunk to the length of the inter-food interval. Wistar and WKY rats displayed maximum drinking under an FT 15-s schedule, with WKY rats registering lower quantities across all FT values. Among SHR rats, maximum schedule-induced polydipsia was observed under the FT 30-s schedule, with a rightward shift in the bitonic function compared to controls. For long FT values, the temporal distribution of licks within inter-food intervals was shifted slightly towards the right in the SHR rats. In a subsequent study, only the SHR and Wistar rats were used, and the animals were exposed to a delay-discounting procedure. The rats were faced with successive choices, in which they could choose between an immediate reward of one food pellet and another of four food pellets at a delay of 3, 6, 12 or 24 s. In the case of the longer delays, SHR rats chose the immediate reward of lower magnitude more often than did their Wistar counterparts, and also committed a greater number of omissions during the forced-choice trials of the procedure. The results indicate that differences in schedule-induced polydipsia are related to indexes of cognitive rather than motor impulsivity, a finding in line with the theoretical idea that adjunctive behaviour is linked to operant reinforcement processes.     

Androgen levels and anger and impulsivity measures as predictors of physical, verbal and indirect aggression in boys and girls

Previous studies indicate that androgen levels and certain psychological characteristics such as anger and impulsivity are related to the development and maintenance of aggression. Further studies are required to analyze the potential predictor role of the interaction of said factors on aggressive behavior. 90 nine-year-old children (44 boys and 46 girls) were assessed in relation to their levels of physical, verbal and indirect aggression, using a peer-rating technique. Testosterone and androstenedione levels were analyzed using an enzymoimmunoassay technique in saliva samples. Anger (state and trait) and anger control were measured using the STAXI-NA, and impulsivity was measured through the MFF-20. A General Linear Model revealed that sex was the best predictor for aggression measures, with boys scoring higher than girls in physical, verbal and indirect aggression; after sex, testosterone was found to be the best predictor (in a positive sense) of all three types of aggressive behavior studied. In addition to observing a main effect of androstenedione on physical and verbal aggression, a 'state anger*androstenedione' interaction was found to predict these types of aggression, with androstenedione acting as a moderator (inhibitor) of the effects of anger on these behaviors; also, a 'state anger*testosterone' interaction was found to predict verbal aggression. The results support the idea that, after sex, androgens constitute a biological marker to be taken into consideration in relation to individual differences in aggressive behavior. It is possible that at the age of 9, testosterone tends to increase aggression, while androstenedione tends to moderate (inhibit) the effects of anger on aggression.     

The short (S) allele of the serotonin transporter polymorphism and acute tryptophan depletion both increase impulsivity in men

Reduced serotonergic neurotransmission is implicated in impulsive behavior. We studied the triallelic system of the serotonin transporter gene linked polymorphic region (5-HTTLPR) and acute manipulation of serotonin together to further delineate the mechanisms by which serotonergic neurotransmission affects impulsivity. Fifty-two healthy participants (38 men and 14 women) underwent acute tryptophan depletion (ATD) or placebo in a randomized, double-blind, parallel group experiment. Impulsive response style was measured on two versions of the Continuous Performance Task (CPT), and calculated using signal detection theory. We observed a dose-dependent effect for the short (S′) allele of the 5-HTTLPR on impulsive response style. Individuals who had the S′/S′ genotype were more impulsive than individuals with the L/S′ genotype. Participants with the L/S′ genotype were more impulsive than those with the L/L genotype. ATD increased impulsivity in men, and decreased impulsivity in women. These data demonstrate for the first time that reduced serotonergic tone as a result of either 5-HTTLPR genotype, or experimental ATD, are both independently and additively, associated with elevated impulsive response style in Caucasian men.     

网络成瘾住院患者冲动、攻击性人格特点及治疗转归

目的 了解网络成瘾住院患者冲动、攻击性人格特点以及经过综合性网瘾戒治后转归情况.方法 采用Barratt冲动性量表(BIS)、Buss行为攻击问卷(BAS)、症状自评量表(SCL-90)分别对58例网络成瘾住院患者在入院1周内和综合性网瘾戒治3月后进行评估,并与54例正常对照比较.结果 ①IAD组治疗前冲动、攻击量表各因子分以及总分均比正常对照组高[BIS评分(99.3±15.1)分,(75.0±15.4)分,t=8.47,P＜0.01;BAS评分(78.3±24.4)分,(54.8±17.7)分,t=5.87,P＜0.01];治疗后冲动、攻击量表除躯体攻击外,其余各因子分以及总分明显降低但仍比正常对照高[BIS评分(86.3±16.6)分,(75.0±15.4)分,t=4.98,P＜0.01;BAS评分(66.2±22.6)分,(54.8±17.7)分,t=3.65,P＜0.01];②IAD组SCL-90总分与BAS量表总分存在显著相关性(r=0.376,P＜0.01),治疗后SCL-90总分降低值与BAS降低值亦存在相关(r=0.508,P＜0.01).结论 网络成瘾组冲动、攻击性比正常对照组高,经治疗后其冲动、攻击性降低,但仍高于对照组.

Abstract：

Objective To explore the impulsivity and aggressivity,and its treatment outcomes of the inpatients with intemet addiction disorder (IAD) by intergration interview. Methods Barratt Impulsiveness Scale ( BIS), Buss Aggressive Scale (BAS) were used to assess the impulsiveness and aggressivity in 58 IAD patients, at the first week and after the point of intergration interview 3 months,54 normal subjects in the control group were conducted by BIS and BAS only when they were recruited. Results ①The intemet addiction group had significantly higher scores on the BIS and BAS total scores than the control group at the first week ( BIS score 99.3 ±15. 1vs 75.0 ± 15.4, t=8.47, P＜0. 01; BAS score 78.3 ±24.4 vs 54.8 ± 17.7, t=5.87 , P＜0. 01 ). IAD group had lower scores on the total scores of BIS-Ⅱ and BAS after intergration interview than before, but the subscales and total scores were higher than those in the control group ( BIS score 86.3 ± 16.6 vs 75.0 ± 15.4, t =4.98, P ＜ 0.01 ;BAS score 66.2 ± 22.6 vs 54.8 ± 17.7, t = 3.65, P ＜ 0. 01 ). ②Total score of SCL-90 in IAD group were significantly correlated with the BAS total score ( r=0. 376, P＜0. 01 ) ,and the decreased SCL-90 total score was also related with the decreased BAS score ( r= 0.508, P＜ 0. 01 ). Conclusion This study suggests that IAD group exhibit more impulsivity and aggressivity than those in the control group. After interview, their impulsivity and aggressivity are significantly decreased, but are still higher than those in the normal control group.     

Impulsivity and test meal intake in obese binge eating women

Greater impulsivity has been observed in those with chemical (cocaine, marijuana, alcohol) and behavioral addictions (gambling, sex, shopping), as well as in individuals with personality and conduct disorders. Greater impulsivity has also been described in those with Bulimia Nervosa and attributed to aberrations in serotonin, as has eating in response to negative affect. However, less is known about the impact of impulsivity on eating behavior in obese humans in general, and in those who meet sub-clinical and full clinical criteria for Binge Eating Disorder (BED) in particular. Using a laboratory test meal paradigm, we demonstrated: (1) greater Motor Impulsivity (Barratt Impulsivity Scale (BIS) (p = 0.05) in those with BED (n = 11) as compared to those without BED (n = 11) (2) a positive correlation between BED criteria and BIS scores (p < 0.01) (3) a positive correlation between test meal duration and Zung Depression Score, and (4) a positive correlation between Motor Impulsivity and mood rated before consuming the test meal. These associations suggest potential aberrations in serotonin transmission in BED, and a possible target for pharmacotherapy of BED especially in those who are resistant to Cognitive Behavioral Therapy.