Microbes Contribute to Chemopreventive Efficacy, Intestinal Tumorigenesis, and the Metabolome.

Bacteria are believed to play an important role in intestinal tumorigenesis and contribute to both gut luminal and circulating metabolites. Celecoxib, a selective cyclooxygenase-2 inhibitor, alters gut bacteria and metabolites in association with suppressing the development of intestinal polyps in mice. The current study sought to evaluate whether celecoxib exerts its chemopreventive effects, in part, through intestinal bacteria and metabolomic alterations. Using ApcMin/+ mice, we demonstrated that treatment with broad-spectrum antibiotics (ABx) reduced abundance of gut bacteria and attenuated the ability of celecoxib to suppress intestinal tumorigenesis. Use of ABx also impaired celecoxib's ability to shift microbial populations and gut luminal and circulating metabolites. Treatment with ABx alone markedly reduced tumor number and size in ApcMin/+ mice, in conjunction with profoundly altering the metabolite profiles of the intestinal lumen and blood. Many of the metabolite changes in the gut and circulation overlapped and included shifts in microbially derived metabolites. To complement these findings in mice, we evaluated the effects of ABx on circulating metabolites in patients with colon cancer. This showed that ABx treatment led to a shift in blood metabolites, including several that were of bacterial origin. Importantly, changes in metabolites in patients given ABx overlapped with alterations found in mice that also received ABx. Taken together, these findings suggest a potential role for bacterial metabolites in mediating both the chemopreventive effects of celecoxib and intestinal tumor growth. PREVENTION RELEVANCE: This study demonstrates novel mechanisms by which chemopreventive agents exert their effects and gut microbiota impact intestinal tumor development. These findings have the potential to lead to improved cancer prevention strategies by modulating microbes and their metabolites.

The Sensitivity of Clinical Outcomes to Centration on the Light-Constricted Pupil for a Shape-Changing Corneal Inlay.

PURPOSE: To assess the clinically acceptable range of inlay decentration with respect to the light-constricted pupil center and the coaxially sighted corneal light reflex (CSCLR) for an inlay (Raindrop Near Vision Inlay; ReVision Optics, Inc., Lake Forest, CA) that reshapes the anterior corneal surface. METHODS: In this retrospective, observational cohort study of 115 patients with emmetropic or low hyperopic presbyopia who were implanted with a shape-changing corneal inlay, visual acuity, task performance (in good and dim light), reports of halos and glare, and satisfaction data were collected from the preoperative and 3-month postoperative examinations. Inlay centration with respect to the pupil center and CSCLR was determined from the center of the inlay effect derived from iTrace (Tracey Technologies, Houston, TX) wavefront measurements. Multivariate regression models assessed the influence of inlay position on visual outcomes. RESULTS: On average, monocular uncorrected near visual acuity (UNVA) improved 4.9 ± 1.7 lines in the treated eye, with no loss in binocular distance vision. Eighty-three percent of implants were centered radially within 0.5 mm of the pupil center. Multivariate analysis of decentration with respect to both the pupil center and CSCLR revealed no significant interaction with the above clinical outcomes, with the exception of UNVA in the treated eye (all P > .05, α = 0.05). For decentration of less than 0.75 mm, the change in UNVA was less than 1 line. CONCLUSIONS: Distance and near visual acuity, task performance, severity of halos and glare, and satisfaction were independent of radial decentration of the Raindrop Near Vision Inlay of less than 0.75 mm from the light-constricted pupil. [J Refract Surg. 2018;34(3):164-170.].

Corneal remodeling after implantation of a shape-changing inlay concurrent with myopic or hyperopic laser in situ keratomileusis.

PURPOSE: To compare the induced addition (add)-power profile and epithelial remodeling between patients receiving hyperopic and myopic laser in situ keratomileusis (LASIK) concurrently with implantation of a corneal shape-changing inlay. SETTING: Specialty clinics in Monterrey and Tijuana, Mexico. DESIGN: Retrospective case series. METHODS: Preoperative hyperopic patients (mean spherical equivalent [SE] treatment +1.71 diopters [D] ± 0.51 [SD]) and myopic patients (mean SE treatment -2.48 ± 1.33 D) had implantation of a Raindrop Near Vision Inlay in the nondominant eye immediately after the excimer laser ablation in both eyes under a corneal flap. Monocular and binocular visual acuities were recorded at 6 m. Wavefront measurement analysis yielded the mean inlay add-power profile, and optical coherence tomography images yielded the mean epithelial remodeling profile. RESULTS: In the inlay eye in the hyperopic group (n = 34) and myopic group (n = 29), the mean uncorrected near visual acuity exceeded 20/25 (85% 20/25 or better), the mean uncorrected distance visual acuity (UDVA) was 20/32 (62% 20/32 or better), and the mean binocular UDVA was 20/18 (100% 20/25 or better). The add-power profiles for the hyperopic and myopic groups were similar. The epithelial thinning profiles were also the same, thinning centrally by approximately 19 µm, and were uncorrelated with the treated refractive error. CONCLUSIONS: After concurrent LASIK and inlay implantation, the visual acuity, induced add-power profile, and epithelial remodeling were the same, regardless of hyperopic or myopic treatment.

Structural Changes Induced by a Corneal Shape-Changing Inlay, Deduced From Optical Coherence Tomography and Wavefront Measurements.

PURPOSE: Changes to the anterior stroma and epithelium induced by a meniscus-shaped corneal inlay are presented. The hypothesis that local curvature is a driver of epithelial remodeling is tested. METHODS: Records of 30 subjects enrolled in a prospective clinical investigation of the inlay, implanted in emmetropic presbyopic subjects, were analyzed. The change to the anterior corneal surface was measured using wavefront techniques. The epithelial thinning profile was measured using Fourier domain optical coherence tomography. The stromal change was calculated from the two measurements. RESULTS: The inlay's volume displaced the stroma anterior to the inlay, which was reflected in the change of Bowman's layer shape. The epithelium anterior to the inlay thinned by 18.4 ± 7.1 µm. Peripheral to the inlay's diameter (2 mm), circumferential epithelial thickening extended the change to the anterior corneal surface to approximately twice the inlay diameter. The central anterior corneal surface rose by 9.8 ± 3.4 µm, creating a progressive add power profile. The epithelial thinning was linearly related to the curvature of the alteration to the anterior surface height, consistent with a theoretical model. CONCLUSIONS: When a meniscus-shaped corneal inlay is placed beneath a corneal flap, the flap's stroma takes on predominately the inlay's shape. The epithelium remodels within a zone approximately twice the inlay diameter, with an anterior corneal height change providing improved near and intermediate vision. The relationship between the epithelial, stromal, and anterior corneal surface changes confirms the hypothesis that epithelial changes are greatest in regions of greater local surface curvature.

Range of refractive independence and mechanism of action of a corneal shape-changing hydrogel inlay: results and theory.

PURPOSE: To demonstrate the independence of visual performance over a range of preoperative refraction and age in presbyopes implanted with a corneal shape-changing inlay (Raindrop Near Vision Inlay). SETTING: Two multispecialty clinics, Monterrey and Tijuana, Mexico. DESIGN: Prospective case series. METHODS: The nondominant eyes of patients were implanted with the hydrogel corneal inlay beneath a femtosecond flap, centered on the pupil. Clinical outcomes included uncorrected near, intermediate, and distance visual acuity (UNVA, UIVA, and UDVA) and patient-assessed task performance in good light and dim light. Statistical analyses assessed the dependencies on preoperative age (45 to 60 years) and preoperative manifest refraction spherical equivalent (MRSE) (-0.5 to +1.5 diopters [D]). Using the inlay effect derived from wavefront measurements, an eye model was created through which letter charts were simulated. RESULTS: The study evaluated eyes of 188 patients. Postoperative UNVA, UIVA, and task performance at these distances in good light was independent of age and preoperative MRSE (P > .05). Postoperative UDVA was weakly dependent on preoperative MRSE, but distance task performance in good light was not (P > .05). In the treated eye, the mean postoperative UNVA was 20/25, UIVA was 20/25, and UDVA was 20/32. The clinical outcomes are explained by consideration of zones within the pupil generating good near, intermediate, and distance image quality. This was confirmed by visual acuity simulations. CONCLUSIONS: The continuous center-near power profile induced by the corneal shape-changing inlay provides good visual acuity and performance from distance through near over a 2.0 D range of preoperative refraction and presbyopic age. FINANCIAL DISCLOSURE: Drs. Steinert, Schwiegerling, Barragán-Garza, and Chayet are consultants to Revision Optics, Inc. Drs. Lang and Holliday and Mr. Roy are employees of Revision Optics, Inc. Drs. Steinert, Schwiegerling, Barragán-Garza, and Chayet have no financial or proprietary interest in any material or method mentioned.

Ambivalence Model of Craving: A Latent Profile Analysis of Cue-Elicited Alcohol Craving in an Inpatient Clinical Sample.

OBJECTIVE: Craving has been defined as intense desires or urges to consume alcohol and is considered predictive of future drinking and relapse. Despite this assumption, research on the craving-drinking relationship has been mixed, calling into question how researchers define and measure craving. The primary aim of the current study was to examine a promising, but understudied, model of craving (Ambivalence Model of Craving [AMC]) that calls for the concurrent assessment of both approach (desires to use) and avoidance (desires to not use) inclinations. METHOD: Participants (N = 175) were recruited from an acute detoxification facility. Alcohol craving was evaluated with a cue-reactivity paradigm in which participants viewed substance cue slides and separately rated their desire to consume and not consume the substance after each image. Latent profile analysis examined distinct motivational profiles for alcohol predicted by the AMC: ambivalence (high approach, high avoidance), indifference (low approach, low avoidance), approach (high approach, low avoidance), and avoidance (low approach, high avoidance). RESULTS: Latent classes corresponded to the AMC, but a fifth class differentiated moderate versus high ambivalence. Classes were associated with auxiliary variables in predicted directions; high ambivalence and approach classes were associated with greater drinking and negative consequences, whereas voluntary admittance to treatment was more likely with ambivalence and avoidance classes. CONCLUSIONS: The AMC provides a promising framework for evaluating cue-elicited craving and alcohol use in clinical samples and may be a useful model of craving for clinicians during treatment.

Psychometric Evaluation of the Substance Use Risk Profile Scale (SURPS) in an Inpatient Sample of Substance Users Using Cue-Reactivity Methodology.

The current project sought to examine the psychometric properties of a personality based measure (Substance Use Risk Profile Scale; SURPS: introversion-hopelessness, anxiety sensitivity, impulsivity, and sensation seeking) designed to differentially predict substance use preferences and patterns by matching primary personality-based motives for use to the specific effects of various psychoactive substances. Specifically, we sought to validate the SURPS in a clinical sample of substance users using cue reactivity methodology to assess current inclinations to consume a wide range of psychoactive substances. Using confirmatory factor analysis and correlational analyses, the SURPS demonstrated good psychometric properties and construct validity. Further, impulsivity and sensation-seeking were associated with use of multiple substances but could be differentiated by motives for use and susceptibility to the reinforcing effects of stimulants (i.e., impulsivity) and alcohol (i.e. sensation-seeking). In contrast, introversion-hopelessness and anxiety sensitivity demonstrated a pattern of use more focused on reducing negative affect, but were not differentiated based on specific patterns of use. Taken together, results suggests that among those receiving inpatient treatment for substance use disorders, the SURPS is a valid instrument for measuring four distinct personality dimensions that may be sensitive to motivational susceptibilities to specific patterns of alcohol and drug use.

Women Inmate Substance Abusers' Reactivity to Visual Alcohol, Cigarette, Marijuana, and Crack-Cocaine Cues: Approach and Avoidance as Separate Dimensions of Reactivity.

Despite the growing recognition for multidimensional assessments of cue-elicited craving, few studies have attempted to measure multiple response domains associated with craving. The present study evaluated the Ambivalence Model of Craving (Breiner et al., 1999; Stritzke et al., 2007) using a unique cue reactivity methodology designed to capture both the desire to use (approach inclination) and desire to not consume (avoidance inclination) in a clinical sample of incarcerated female substance abusers. Participants were 155 incarcerated women who were participating in or waiting to begin participation in a nine-month drug treatment program. Results indicated that all four substance cue-types (alcohol, cigarette, marijuana, and crack cocaine) had good reliability and showed high specificity. Also, the validity of measuring approach and avoidance as separate dimensions was supported, as demonstrated by meaningful clinical distinctions between groups evincing different reactivity patterns and incremental prediction of avoidance inclinations on measures of stages of change readiness. Taken together, results continue to highlight the importance of measuring both approach and avoidance inclinations in the study of cue-elicited craving.

Stress-induced drinking in parents of boys with attention-deficit-hyperactivity disorder: heterogeneous groups in an experimental study of adult-child interactions.

Research on whether parents of children with externalizing disorders are at elevated risk for alcohol problems is equivocal. To reduce this ambiguity, we examined how individual differences in stress reactivity might moderate the drinking behavior of such parents. Parents (119 mothers, 44 fathers) of ADHD sons interacted with different child confederates during each of two counter-balanced sessions. In one, the confederate portrayed a friendly, cooperative, "normal" boy; in the other, the confederate portrayed a "deviant" boy who exhibited behavior characteristic of externalizing disorders. Following each interaction, parents were given an opportunity for ad lib consumption of alcohol while anticipating a second interaction. Latent class analysis identified three subgroups of parents using distress scores and alcohol consumption: minimal stress reactivity; reacts to child deviance with increased distress, but not increased drinking; marked stress-induced drinking. Decisions about the nature and proper treatment of parents raising children with ADHD may be compromised by failure to attend to individual differences in stress reactivity and inclinations to use drinking to cope.

Affect and craving: positive and negative affect are differentially associated with approach and avoidance inclinations.

BACKGROUND: Research on reactivity to alcohol and drug cues has either ignored affective state altogether or has focused rather narrowly on the role of negative affect in craving. Moreover, until recently, the relevant analyses of affect and craving have rarely addressed the ambivalence often associated with craving itself. The current study investigated how both negative and positive affect moderate approach and avoidance inclinations associated with cue-elicited craving in a clinical sample diagnosed with substance use disorders. METHODS: One hundred forty-four patients (age range of 18-65, mean 42.0; n=92 males) were recruited from an inpatient detoxification unit for substance abuse. Participants completed a baseline assessment of both positive and negative affect prior to completing a cue-reactivity paradigm for which they provided self-report ratings of inclinations to approach (use) and avoid (not use) alcohol, cigarettes, and non-psychoactive control substances (food and beverages). RESULTS: Participants with elevated negative affect reported significantly higher approach ratings for cigarette and alcohol cues, whereas those high in positive affect showed significantly higher levels of avoidance inclinations for both alcohol and cigarette cues and also significantly lower approach ratings for alcohol cues, all relative to control cues. CONCLUSIONS: Results for negative affect are consistent with previous cue reactivity research, whereas results for positive affect are unique and call attention to its clinical potential for attenuating approach inclinations to substance use cues. Further, positive affect was related to both approach and avoidance inclinations, underscoring the utility of a multidimensional conceptualization of craving in the analysis.

Effects of acute alcohol intoxication on automated processing: evidence from the double-step paradigm.

Reflexive and voluntary levels of processing have been studied extensively with respect to possible impairments due to alcohol intoxication. This study examined alcohol effects at the 'automated' level of processing essential to many complex visual processing tasks (e.g., reading, visual search) that involve ongoing modifications or reprogramming of well-practiced routines. Data from 30 participants (16 male) were collected in two counterbalanced sessions (alcohol vs. no-alcohol control; mean breath alcohol concentration = 68 mg/dL vs. 0 mg/dL). Eye movements were recorded during a double-step task where 75% of trials involved two target stimuli in rapid succession (inter-stimulus interval [ISI]=40, 70, or 100 ms) so that they could elicit two distinct saccades or eye movements (double steps). On 25% of trials a single target appeared. Results indicated that saccade latencies were longer under alcohol. In addition, the proportion of single-step responses and the mean saccade amplitude (length) of primary saccades decreased significantly with increasing ISI. The key novel finding, however, was that the reprogramming time needed to cancel the first saccade and adjust saccade amplitude was extended significantly by alcohol. The additional time made available by prolonged latencies due to alcohol was not utilized by the saccade programming system to decrease the number of two-step responses. These results represent the first demonstration of specific alcohol-induced programming deficits at the automated level of oculomotor processing.

Alcohol impairs brain reactivity to explicit loss feedback.

RATIONALE: Alcohol impairs the brain's detection of performance errors as evidenced by attenuated error-related negativity (ERN), an event-related potential (ERP) thought to reflect a brain system that monitors one's behavior. However, it remains unclear whether alcohol impairs performance-monitoring capacity across a broader range of contexts, including those entailing external feedback. OBJECTIVE: This study sought to determine whether alcohol-related monitoring deficits are specific to internal recognition of errors (reflected by the ERN) or occur also in external cuing contexts. We evaluated the impact of alcohol consumption on the feedback-related negativity (FRN), an ERP thought to engage a similar process as the ERN but elicited by negative performance feedback in the environment. METHODS: In an undergraduate sample randomly assigned to drink alcohol (n = 37; average peak BAC = 0.087 g/100 ml, estimated from breath alcohol sampling) or placebo beverages (n = 42), ERP responses to gain and loss feedback were measured during a two-choice gambling task. Time-frequency analysis was used to parse the overlapping theta-FRN and delta-P3 and clarified the effects of alcohol on the measures. RESULTS: Alcohol intoxication attenuated both the theta-FRN and delta-P3 brain responses to feedback. The theta-FRN attenuation was stronger following loss than gain feedback. CONCLUSIONS: Attenuation of both theta-FRN and delta-P3 components indicates that alcohol pervasively attenuates the brain's response to feedback in this task. That theta-FRN attenuation was stronger following loss trials is consistent with prior ERN findings and suggests that alcohol broadly impairs the brain's recognition of negative performance outcomes across differing contexts.

A meta-analysis of the effectiveness of placebo manipulations in alcohol-challenge studies.

Our meta-analysis examined the impact of specific alcohol placebo procedures on two manipulation checks (participant reports of number of alcohol drinks consumed and subjective intoxication) to determine which procedures produced the smallest effect sizes in comparisons between alcohol and placebo conditions. Databases for the years 1990-2007 yielded 44 studies that met inclusion criteria. These were subjected to detailed coding of procedures pertinent to placebo effectiveness. Alcohol versus placebo condition comparisons generally produced large effect sizes for both manipulation checks, but they were moderated by double-blind procedures and by peak breath-alcohol concentration (BrAC) attained in the alcohol condition. Other procedures moderated only the estimated number of alcohol drinks consumed. Implications for selection and assessment of alcohol placebo manipulations and for interpretability of experiments using them are discussed.

Effect of alcohol on race-biased responding: the moderating role of internal and external motivations to respond without prejudice.

OBJECTIVE: This experiment was a systematic examination of how drinking, available response time, and levels of internal and external motivations to respond without prejudice interact to affect responses in a behavioral assessment of the race bias of social drinkers. METHOD: Ninety-one white undergraduate social drinkers (45 women) were randomly assigned within gender to alcohol (expect alcohol/receive alcohol), placebo (expect alcohol/receive placebo), or simple no-alcohol control (expect no alcohol/receive no alcohol) conditions. Participants then performed a sequential priming task, the Weapons Identification Task, designed to assess race-biased responding, under nonspeeded (2,000 ms) or speeded (500 ms) instructional sets. RESULTS: Relative to both placebo and simple no-alcohol control groups, participants who consumed alcohol to an average peak breath alcohol concentration of .08 exhibited higher rates of race-biased errors but only under speeded conditions. Further, this effect was moderated by individual differences such that alcohol-induced, race-biased errors were elevated among all participants, except those whose motives to respond without prejudice were primarily internal. Personal motivations to respond without prejudice also moderated the responses of participants in the placebo group, such that those restrained primarily by external concerns uniquely evinced more race-biased errors than participants in the other motive groups. CONCLUSIONS: Both alcohol intoxication and alcohol expectancy can increase race-biased errors but only under speeded conditions and in a manner moderated by participants' levels of internal and external motives to respond without prejudice.

Specificity of social anxiety disorder as a risk factor for alcohol and cannabis dependence.

Social anxiety disorder (SAD) is highly comorbid with alcohol use disorders (AUDs) and cannabis dependence. However, the temporal sequencing of these disorders has not been extensively studied to determine whether SAD serves as a specific risk factor for problematic substance use. The present study examined these relationships after controlling for theoretically-relevant variables (e.g., gender, other Axis I pathology) in a longitudinal cohort over approximately 14 years. The sample was drawn from participants in the Oregon Adolescent Depression Project. After excluding those with substance use disorders at baseline, SAD at study entry was associated with 6.5 greater odds of cannabis dependence (but not abuse) and 4.5 greater odds of alcohol dependence (but not abuse) at follow-up after controlling for relevant variables (e.g., gender, depression, conduct disorder). The relationship between SAD and alcohol and cannabis dependence remained even after controlling for other anxiety disorders. Other anxiety disorders and mood disorders were not associated with subsequent cannabis or alcohol use disorder after controlling for relevant variables. Among the internalizing disorders, SAD appears to serve as a unique risk factor for the subsequent onset of cannabis and alcohol dependence.

Specific visuomotor deficits due to alcohol intoxication: evidence from the pro- and antisaccade paradigms.

RATIONALE: Alcohol affects a variety of human behaviors, including visual perception and motor control. Although recent research has begun to explore mechanisms that mediate these changes, their exact nature is still not well understood. OBJECTIVES: The present study used two basic oculomotor tasks to examine the effect of alcohol on different levels of visual processing within the same individuals. A theoretical framework is offered to integrate findings across multiple levels of oculomotor control. MATERIALS AND METHODS: Twenty-four healthy participants were asked to perform eye movements in reflexive (pro-) and voluntary (anti-) saccade tasks. In one of two counterbalanced sessions, performance was measured after alcohol administration (mean BrAC=69 mg%); the other served as a within-subjects no-alcohol comparison condition. RESULTS: Error rates were not influenced by alcohol intoxication in either task. However, there were significant effects of alcohol on saccade latency and peak velocity in both tasks. Critically, a specific alcohol-induced impairment (hypermetria) in saccade amplitudes was observed exclusively in the anti-saccade task. CONCLUSIONS: The saccade latency data strongly suggest that alcohol intoxication impairs temporal aspects of saccade generation, irrespective of the level of processing triggering the saccade. The absence of effects on anti-saccade errors calls for further research into the notion of alcohol-induced impairment of the ability to inhibit prepotent responses. Furthermore, the specific impairment of saccade amplitude in the anti-saccade task under alcohol suggests that higher level processes involved in the spatial remapping of target location in the absence of a visually specified saccade goal are specifically affected by alcohol intoxication.

Intoxication level and emotional response.

We used affective modulation of the eye-blink component of the startle reflex to examine effects of three levels of alcohol intoxication and a no-intoxication control on emotional responses to pleasant, neutral, and unpleasant pictures. Non-problematic student drinkers (n=101; 48 female) were randomly assigned to intoxication groups. Normal inhibition of startle during exposure to pleasant pictures was intact across groups. In contrast, potentiation of startle during viewing of unpleasant pictures was evident in the no- and low-intoxication groups, compared to the intermediate- and high-intoxication groups, in which it was significantly reduced. This pattern suggests that a direct and selective anxiolytic effect of alcohol can occur at higher levels of intoxication without an analogous impact on response to emotionally positive stimuli at similar levels.

Relations between psychopathy facets and externalizing in a criminal offender sample.

The construct of psychopathy is viewed as comprising distinctive but correlated affective-interpersonal and social deviance facets. Here, we examined these facets of Hare's Psychopathy Checklist-Revised (PCL-R) in terms of their associations with the externalizing dimension of adult psychopathology, defined as the common factor underlying symptoms of conduct disorder, adult antisocial behavior, alcohol use/abuse, and drug abuse, along with disinhibitory personality traits. Correlational analyses revealed a strong relationship between this externalizing dimension and the social deviance facet of psychopathy (r = .84), and a lesser relationship with the emotional-interpersonal component (r = .44). Structural models controlling for the moderate overlap between the PCL-R factors revealed that externalizing was substantially related to the unique variance in the social deviance features of psychopathy, but unrelated to the unique variance of the emotional and interpersonal features whether modeled together or as separate factors. These results indicate that the social deviance factor of the PCL-R reflects the externalizing dimension of psychopathology, whereas the emotional-interpersonal component taps something distinct aside from externalizing. In addition, based on our finding of an association between PCL-R social deviance and externalizing, we were able to predict new relations between this facet of psychopathy and criterion variables, including nicotine use and gambling, that have previously been linked to externalizing. Implications for future research on the causes and correlates of psychopathy are discussed.

Assessment of substance cue reactivity: advances in reliability, specificity, and validity.

An arousal-control and cross-over design was used to evaluate the reliability, specificity, and validity of the Normative Appetitive Picture System (NAPS), a cue exposure protocol with sets of visual alcohol, cigarette, and control cues. The authors also examined the utility of conceptualizing cue reactivity as a multidimensional phenomenon involving independent approach and avoidance dimensions. University student participants (n=369) rated multiple cue images in terms of arousing properties and capacity to elicit separate approach and avoidance inclinations. They also completed a battery of substance-related individual-difference measures. Results indicated that NAPS protocol reactivity profiles had good reliability and high specificity across cue types and individuals with different substance use histories. Avoidance reactivity independently predicted self-reports of substance-related behaviors, after controlling for approach reactivity.

Emotional modulation of the post-auricular reflex.

A large literature now exists on emotional modulation of the startle blink reflex. The current study examined affective modulation of the post-auricular reflex, which can be measured in relation to the same noise probe used to evoke the startle reflex. We recorded the post-auricular reflex during viewing of pictures that varied systematically in emotional valence, content, and intensity. A significant linear valence modulation effect was found, with pleasant pictures potentiating and aversive pictures inhibiting the post-auricular reflex in comparison with neutral pictures. This modulatory effect did not vary as a function of picture content, but it was most robust for highly intense emotional pictures. Implications for the assessment of basic emotional action tendencies are discussed.