Eduardo Blanco

Affective modulation of the startle reflex and the Reinforcement Sensitivity Theory of personality: The role of sensitivity to reward.

This study evaluated differences in the amplitude of startle reflex and Sensitivity to Reward (SR) and Sensitivity to Punishment (SP) personality variables of the Reinforcement Sensitivity Theory (RST). We hypothesized that subjects with higher scores in SR would obtain a higher startle reflex when exposed to pleasant pictures than lower scores, while higher scores in SP would obtain a higher startle reflex when exposed to unpleasant pictures than subjects with lower scores in this dimension. The sample consisted of 112 healthy female undergraduate psychology students. Personality was assessed using the short version of the Sensitivity to Punishment and Sensitivity Reward Questionnaire (SPSRQ). Laboratory anxiety was controlled by the State Anxiety Inventory. The startle blink reflex was recorded electromyographically (EMG) from the right orbicularis oculi muscle as a response to the International Affective Picture System (IAPS) pleasant, neutral and unpleasant pictures. Subjects higher in SR obtained a significant higher startle reflex response in pleasant pictures than lower scorers (48.48 vs 46.28, p<0.012). Subjects with higher scores in SP showed a light tendency of higher startle responses in unpleasant pictures in a non-parametric local regression graphical analysis (LOESS). The findings shed light on the relationships among the impulsive-disinhibited personality, including sensitivity to reward and emotions evoked through pictures of emotional content.

Interactions among impulsiveness, testosterone, sex hormone binding globulin and androgen receptor gene CAG repeat length.

Impulsive personality phenotype has been extensively related with genetic and hormonal factors. This study has two objectives: a) to analyse the interactions between testosterone levels and CAG repeat length polymorphism as a modulator of androgen receptor (AR) sensitivity with regard to impulsiveness traits, and b) to evaluate the contribution of other biological variables as Luteinising Hormone, Follicle Stimulating Hormone, Sex Hormone Binding Globulin (LF, FSH, SHBG) and albumin in the relationship between testosterone levels and AR CAG length polymorphism with impulsiveness. A sample of 105 healthy males (mean age 26.71±9.68 SEM) was analysed resulting in three groups of subjects according to CAG repeat lengths. Impulsiveness was measured through the Barratts Impulsiveness Personality Scale, including three components: Motor Impulsiveness, Cognitive Impulsiveness and Non-Planning Impulsiveness. A series of ANOVAS and linear regression models predicting impulsiveness scales were conducted. Age, hormones, CAG repeat length and hormone×CAG repeat interactions were included in the regression models as independent variables. Results show that subjects with short or medium CAG repeat length tended to show higher impulsiveness phenotypes compared to long CAG repeat. The interaction between Free Testosterone and CAG, and between SHBG and CAG accounted for differences on impulsiveness (R: .47, R(2): .22 and R: .43; R(2): .18, respectively).This pattern was especially observed for the short CAG repeat group and Motor Impulsiveness.

The Dimensional Assessment of Personality Psychopathology Basic Questionnaire: shortened versions item analysis.

This study has been designed to evaluate and replicate the psychometric properties of the Dimensional Assessment of Personality Psychopathology-Basic Questionnaire (DAPP-BQ) and the DAPP-BQ short form (DAPP-SF) in a large Spanish general population sample. Additionally, we have generated a reduced form called DAPP-90, using a strategy based on a structural equation modeling (SEM) methodology in two independent samples, a calibration and a validation sample. The DAPP-90 scales obtained a more satisfactory fit on SEM adjustment values (average: TLI > .97 and RMSEA < .04) respect to full DAPP-BQ and the 136-item version. According to the factorial congruency coefficients, the DAPP-90 obtains a similar structure to the DAPP-BQ and the DAPP-SF. The DAPP-90 internal consistency is acceptable, with a Cronbachs alpha mean of .75. We did not find any differences in the pattern of relations between the two DAPP-BQ shortened versions and the SCL-90-R factors. The new 90-items version is especially useful when it is difficult to use the long version for diverse reasons, such as the assessment of patients in hospital consultation or in brief psychological assessments.

Examining habituation of the startle reflex with the reinforcement sensitivity theory of personality.

The habituation of the acoustic startle reflex (ASR) was examined concerning individual differences in sensitivity to punishment (PUN) and sensitivity to reward (REW), within the general framework of the reinforcement sensitivity theory (RST) of personality. Two hypotheses derived from the RST were evaluated: the separable subsystems hypothesis and the joint subsystems hypothesis. In addition, we examined the direction of the relationship of PUN and REW with the habituation of the ASR. A habituation segment of electromyography recordings of the orbicularis oculi was assessed with an unconditional latent curve model. In accordance with the RST hypotheses, the relationship of PUN and REW on the habituation process was assessed with two conditional latent curve models. There was higher support for the separable subsystems hypothesis. In addition, PUN and REW related with the habituation trajectory of the ASR in the expected directions. Higher levels of PUN and lower levels of REW related with a slower habituation of the ASR, whereas lower levels of PUN and higher levels of REW related with a faster habituation of the ASR.

Inconsistency Index for the Zuckerman-Kuhlman-Aluja Personality Questionnaire (ZKA-PQ)

The purpose of this study is the development of an index to assess inconsistency in the answers of Zuckerman-Kuhlman-Aluja Personality Questionnaire (ZKA-PQ) in order to identify and discard inconsistent subjects in applied psychology, as clinical, forensics, or personnel selection. The procedure consists in the use of 10 pairs of highly correlated items in a wide sample of voluntary and anonymous subjects of both sexes (n = 5.644). We inserted random cases to the original data in order to obtain simulated scores of inconsistency and we established a cut-off criterion to discriminate between consistent and inconsistent subjects according to a 70 T Score. A score higher than 10 points discriminated the 3.7% of the subjects. Cronbach’s alpha average for facets was calculated by ZKA-PQ facets distributed in 8 (&agr;: 0.79), 9–10 (&agr;: 0.67), and above 10 points (&agr;: .50) of the inconsistency index. The Feldt test indicates that alpha differences were significant. The inconsistency score did not affect the factorial structure of the ZKA-PQ. We discussed the utility of this index to identify inconsistent subjects with the ZKA-PQ, as, for instance, those with individual difficulties (a limited vocabulary, poor verbal comprehension, an idiosyncratic way of interpreting item meanings, carelessness, inattentiveness…).

Testosterone and disinhibited personality in healthy males.

The relationship among testosterone (T), free testosterone (FT), bioavailable testosterone (BT) and personality were studied in a sample of 105 healthy males (26.71±9.68years old). The possible effects of age and other hormones, such as luteinizing hormone (LH), follicle-stimulating hormone (FSH), sex hormone binding globulin (SHBG), and albumin (ALB) were controlled. Personality was assessed by the novelty seeking scale of Cloningers Temperament-Character Inventory (TCI), and a reduced version of the Zuckerman-Kuhlman Personality Questionnaire (ZKPQ). Main results show that there is a weak association among three measures of testosterone with novelty seeking, sociability and, to a lesser extent, with impulsive sensation seeking. Our data, as expected, confirmed previous results and also suggest that these relationships are strongly affected by the age variable. LH, FSH and SHBG hormones play no role in the reported relationships.

Palmitoylethanolamide prevents neuroinflammation, reduces astrogliosis and preserves recognition and spatial memory following induction of neonatal anoxia-ischemia

RationalNeonatal anoxia-ischemia (AI) particularly affects the central nervous system. Despite the many treatments that have been tested, none of them has proven to be completely successful. Palmitoylethanolamide (PEA) and oleoylethanolamide (OEA) are acylethanolamides that do not bind to CB1 or CB2 receptors and thus they do not present cannabinoid activity. These molecules are agonist compounds of peroxisome proliferator-activator receptor alpha (PPARα), which modulates the expression of different genes that are related to glucose and lipid metabolism, inflammation, differentiation and proliferation.ObjectiveIn the present study, we analyzed the effects that the administration of PEA or OEA, after a neonatal AI event, has over different areas of the hippocampus.MethodsTo this end, 7-day-old rats were subjected to AI and then treated with vehicle, OEA (2 or 10xa0mg/kg) or PEA (2 or 10xa0mg/kg). At 30xa0days of age, animals were subjected to behavioral tests followed by immunohistochemical studies.ResultsResults showed that neonatal AI was associated with decreased locomotion, as well as recognition and spatial memory impairments. Furthermore, these deficits were accompanied with enhanced neuroinflammation and astrogliosis, as well as a decreased PPARα expression. PEA treatment was able to prevent neuroinflammation, reduce astrogliosis and preserve cognitive functions.ConclusionsThese results indicate that the acylethanolamide PEA may play an important role in the mechanisms underlying neonatal AI, and it could be a good candidate for further studies regarding neonatal AI treatments.

Startle reflex modulation by affective face “Emoji” pictographs

The current research was designed to assess possible differences in the emotional content of pleasant and unpleasant face emoji using acoustically evoked eyeblink startle reflex response. Stimuli were selected from Emojipedia Webpage. First, we assessed these stimuli with a previous independent sample of 190 undergraduate students (46 males and 144 females) mean age of 21.43xa0years (SD 3.89). A principal axis method was performed using the 30 selected emoji faces, extracting two factors (15 pleasant and 15 unpleasant emoji). Second, we measured the acoustic startle reflex modulation in 53 young adult women [mean age 22.13xa0years (SD 4.3)] during the viewing of each of the 30 emoji emotional faces in the context of the theory of motivation and emotion proposed by Lang ( 1995 ), but considering only the valence dimension. We expected to find higher acoustically evoked startle responses when viewing unpleasant emoji and lower responses for pleasant ones, similarly to the results obtained in the studies using human faces as emotional stimulus. An ANOVA was conducted to compare acoustic startle responses associated with pleasant and unpleasant emoji. Results yielded main effects for picture valence ( λ u2009=u20090.80, F (1, 50)u2009=u200912.80, p u2009=u2009.001, η 2 u2009=u20090.20). Post-hoc t test analysis indicated significant differences in the startle response between unpleasant (50.95u2009±u20091.75) and pleasant (49.14u2009±u20092.49) emoji ( t (52)u2009=u20093.59, p u2009=u2009.001), with a Cohen’s d u2009=u20090.495. Viewing affective facial emoji expressions modulates the acoustic startle reflex response according to their emotional content.

Sex differences and personality in the modulation of the acoustic startle reflex

The modulation of the eyeblink component of the acoustic startle reflex (ASR) has been used to study human motivation, attention, and emotion towards affective stimuli of different valence. However, sex and individual differences in personality have been rather overlooked concerning the change in the ASR to brief affective sequences. In this study, we aimed to evaluate sex differences in the ASR, together with the influence of sensitivity to punishment (SP) and sensitivity to reward (SR) in the affective modulation of the ASR to pleasant and unpleasant pictures. We addressed this topic with a latent curve model (LCM) representing the change in the ASR of an extensive group of men (nu202f=u202f166) and women (nu202f=u202f109). There was a significant habituation of the ASR to the pleasant pictures, and a significant sensitization of the ASR to the unpleasant pictures. Both effects were higher and more variable for women than for men. There were in addition interactive and quadratic effects of SP and SR on the ASR to the pleasant and unpleasant pictures. Men and women with extreme scores in SP, and women with low scores in SR habituated faster to the pleasant stimuli. For men scoring low in SP, higher scores in SR related with an attenuated initial ASR to the unpleasant stimuli. Women with extreme scores in SP had a higher initial ASR to the unpleasant stimuli. There were remarkable asymmetries between men and women concerning personality effects on the change in the ASR to affective stimuli.

Palmitoylethanolamide attenuates cocaine-induced behavioral sensitization and conditioned place preference in mice

ABSTRACT Cocaine addiction is a chronically relapsing disorder characterized by compulsive drug‐seeking and drug‐taking behaviors. Previous studies have demonstrated that cocaine, as well as other drugs of abuse, alters the levels of lipid‐based signaling molecules, such as N‐acylethanolamines (NAEs). Moreover, brain levels of NAEs have shown sensitivity to cocaine self‐administration and extinction training in rodents. Given this background, the aim of this study was to investigate the effects of repeated or acute administration of palmitoylethanolamide (PEA), an endogenous NAE, on psychomotor sensitization and cocaine‐induced contextual conditioning. To this end, the potential ability of repeated PEA administration (1 or 10 mg/kg, i.p.) to modulate the acquisition of cocaine‐induced behavioral sensitization (BS) and conditioned place preference (CPP) was assessed in male C57BL/6J mice. In addition, the expression of cocaine‐induced BS and CPP following acute PEA administration were also studied. Results showed that repeated administration of both doses of PEA were able to block the acquisition of cocaine‐induced BS. Furthermore, acute administration of both doses of PEA was able to abolish the expression of BS, while the highest dose also abolished the expression of cocaine‐induced CPP. Taken together, these results indicate that exogenous administration of PEA attenuated psychomotor sensitization, while the effect of PEA in cocaine‐induced CPP depended on whether PEA was administered repeatedly or acutely. These findings could be relevant to understand the role that NAEs play in processes underlying the development and maintenance of cocaine addiction. HighlightsRepeated PEA administration blocks acquisition of cocaine‐conditioned locomotion.Repeated PEA administration blocks acquisition of cocaine sensitization.Acute PEA administration abolishes cocaine sensitization expression.Acquisition of cocaine‐induced CPP is not modulated by repeated PEA administration.Expression of cocaine‐induced CPP is blocked by acute PEA administration.