Natalie A. Ceballos

Body mass index moderates gaze orienting biases and pupil diameter to high and low calorie food images

The primary goal of this study was to examine eye gaze behavior to different kinds of food images in individuals differing in BMI status. Eye-tracking methods were used to examine gaze and pupil responses while normal weight and overweight women freely viewed pairs of different food images: high calorie sweet foods, high calorie savory foods, and low calorie foods. Self-report measures of hunger, state and trait cravings, and restrained eating were also obtained. Results revealed orienting biases to low calorie foods and decreases in pupil diameter to high calorie sweet foods relative to low calorie foods in the overweight group. Groups did not differ in the average amount of time spent gazing at the different image types. Furthermore, increased state cravings were associated with larger pupil diameters to high calorie savory foods, especially in individuals with lower BMIs. In contrast, restrained eating scores were associated with a decreased orienting bias to high calorie sweet foods in the high BMI group. In conclusion, BMI status appears to influence gaze parameters that are less susceptible to cognitive control. Results suggest that overweight individuals, especially those who diet, have negative implicit attitudes toward high calorie foods, especially sweets.

Neurophysiological efficiency in male and female alcoholics

Chronic alcoholics often exhibit impairment in behavioral indicators of cognitive efficiency. However, potential neurophysiological correlates of this deficit are understudied. To examine this function, semantic expectancy was measured by recording the N400 component of the event-related potential (ERP), which is elicited by incongruent semantic information. Abstinent alcoholics, 21-45 days sober (n = 26; 12 males, 14 females), as well as age and education equated community controls (n = 26; 12 males, 14 females), were instructed to read silently 218 sentences ending with either congruent, related/incongruent, or unrelated/incongruent terminal words. Difference waveforms to the terminal word were derived, and amplitude and latency measures of the most negative peak between 300 and 600 ms were obtained. Electrode sites included the midline sites, Fz, Cz, and Pz; the temporal sites T3 and T4; and parietal sites P3 and P4. Significant group effects in amplitude were observed for the difference waveform under the unrelated/incongruent condition at T3, T4, and P4 (P < or = .05). Measures at P3, Pz, Fz, and Cz approached significance (P < or = .15). Although the overall pattern did not change when regression techniques were used to control for age, only the T4 site retained significance (P < or = .05). Across all electrode sites, alcoholics produced reduced N400 amplitudes relative to community controls. Latency was unaffected. There were no group effects for amplitude or latency measures in the related/incongruent condition. These data are consistent with the hypothesis that alcoholics suffer from a subtle deficiency in neurophysiologically based cognitive efficiency which renders them less likely to respond appropriately to irrelevant information.

Borderline personality disorder features in adolescent girls: P300 evidence of altered brain maturation.

OBJECTIVE To examine brain maturation in adolescent girls with borderline personality disorder (BPD) features using the P300 event-related potential. METHODS One hundred twenty-three girls, aged 14-19 yrs, were assigned to one of 4 groups formed by the crossing of BPD features (vs. > or =5 BPD criteria) and median age (vs. >16.5 yrs). P300 responses were measured while subjects performed a complex visual oddball task. RESULTS ANCOVAs of P300 amplitude-adjusting for variability associated with comorbid conduct disorder and depression symptoms--revealed a significant interaction. Among subjects without BPD features, aging was associated with the normal reduction in visual P300 amplitude. Among subjects with BPD features, there were no age-related changes. Additional analyses, which tested the effects of BPD features across the full age range, supported these findings. CONCLUSIONS The present findings suggest abnormal brain maturation among adolescent girls exhibiting features of BPD. SIGNIFICANCE These results support a hypothesis of altered brain maturation in adolescents exhibiting BPD features at an early age. It is suggested that measures of brain maturation obtained during adolescence may improve our ability to predict BPD and comorbid disorders in adulthood.

Tobacco use, alcohol dependence, and cognitive performance.

Chronic alcohol abuse has long been associated with a mild, generalized pattern of cognitive decrements. However, it is important to note that problem drinking rarely occurs in isolation from abuse of other drugs. For people dependent upon alcohol, tobacco is one of the mostly commonly coabused substances. Recent research suggests that individuals with alcohol dependency may gravitate toward tobacco use, in part, because of the positive effects of nicotine on aspects of cognitive performance that may be compromised as a consequence of chronic alcohol misuse. In this article, the author focuses on the effects of nicotine on behavioral and electrophysiological indexes of cognitive performance, and the impact of these effects on alcohol-related cognitive decrements. The author discusses implications of these findings in the context of treatment and recovery of people with alcoholism.

Body Image in Hispanic/Latino vs. European American Adolescents: Implications for Treatment and Prevention of Obesity in Underserved Populations

Hispanic/Latino (H/L) vs. European American (EA) perceptions of current and ideal body image as well as body dissatisfaction were examined in 416 adolescents aged 12–15 years. Gender, culture, and body mass index (BMI) were hypothesized to affect measures of self-perceived body image and dissatisfaction differentially. Participants completed a computerized survey with gender-specific versions of applicable test items. Overall, body dissatisfaction (BD) was higher among EAs vs. H/Ls, females vs. males, and unhealthy BMI vs. healthy BMI (p<.01). A gender × ethnicity interaction trend was also noted (p>.06), in which BD was highest among EA females, followed by H/L females, EA males, and H/L males. Results suggest that gender and cultural differences in body image among adolescents are significant. This study is an important step toward clarifying the nature of weight-related health risks facing the understudied population of Hispanic/Latino teens.

Recent EEG and ERP Findings in Substance Abusers

Research on electroencephalographic (EEG) correlates of substance use has a long history. The present paper provides a review of recent studies −2001 to the present—with a focus on EEG findings in human participants characterized by a history of chronic substance use, abuse or dependence. In some areas (e.g., alcohol and cocaine dependence), the field has attempted to build upon earlier work by incorporating different methodologies or pursuing research questions of a transdisciplinary nature. New areas of inquiry, such as the investigation of EEG differences among users of ecstasy (MDMA) and methamphetamine, have emerged, primarily as a result of an alarming rise in popularity of these drugs.

Nicotine and Cognitive Efficiency in Alcoholics and Illicit Stimulant Abusers: Implications of Smoking Cessation for Substance Users in Treatment

Cigarette smoking is prevalent among alcoholics and illicit substance abusers. However, the potentially confounding effect of nicotine on studies of cognition in detoxified substance users has rarely been addressed. In the current study of 87 participants, behavioral and electrophysiological indices of cognitive efficiency were measured in tobacco smokers from four groups: alcoholics, illicit stimulant abusers, concurrent abusers, and control subjects. Data were collected from 2001 to 2003. We hypothesized that acute nicotine administration would modify cognitive deficits in alcoholics and illicit stimulant abusing groups. An adaptation of the Rapid Visual Information Processing task was administered after stabilization of nicotine levels via a high- or low-dose transdermal nicotine patch. Across groups, increased nicotine dose was associated with decreased reaction time (p =. 03). A group × nicotine dose interaction trend was noted in which increased nicotine was associated with increased correct responding within the alcoholic group (p =. 02). No significant differences in electrophysiology were observed. These results suggest that nicotine may modify cognitive efficiency in alcoholics and illicit stimulant abusers, a concept with relevance to both the design of experimental work and the treatment of alcohol and illicit stimulant dependence. Further work is needed to determine whether this effect predominantly reflects facilitation of cognition function or alleviation of nicotine withdrawal.

Visual-spatial attention in alcoholics and illicit stimulant abusers: effects of nicotine replacement.

Reports of alcohol or illicit drug-related cognitive impairments have frequently disregarded the potentially confounding effects of smoking status and nicotine withdrawal on these measures. This study addressed this issue by measuring visual-spatial attention via an adaptation of the Posner paradigm in three groups of tobacco smokers: controls without a history of alcoholism or illicit drug use (n=27; 20 male), chronic alcoholics (n=22; 18 male), and illicit stimulant abusers (n=36; 21 male). Throughout testing, nicotine levels were stabilized by the double-blind administration of a high (14 or 21 mg) or low (7 mg) dose transdermal nicotine patch. A significant effect of group was observed for number of correct responses to restriction trials (F=5.48, 2/79 df; p=.006). Performance was normalized in the illicit stimulant group, and alcoholic participants exhibited superior performance relative to both illicit stimulant abusers (p=.002) and controls (p=.01). These findings support the hypothesis that nicotine may have a compensatory or normalizing effect on attentional functions in substance abusers. Whether these results reflect the central nervous system-activating effects of nicotine or merely alleviation of nicotine withdrawal is a topic of ongoing research.

Sensorimotor Dysfunction in HIV/AIDS: Effects of Antiretroviral Treatment and Comorbid Psychiatric Disorders

Objectives:Balance and gait problems have repeatedly been mentioned in case descriptions of patients infected with Human Immunodeficiency Virus (HIV-1). Objective evidence of these problems has rarely been reported, however. Furthermore, the extent to which balance and gait are influenced by antiretroviral medications or comorbid psychiatric disorders has rarely been examined. Design:The study compared 78 HIV-1 seronegative volunteers to 28 HIV/AIDS patients receiving no antiretroviral therapy, 25 patients receiving only nucleoside analogue therapy, and 37 patients receiving Highly Active Antiretroviral Therapy (HAART). Methods:The dependent measures included Equilibrium Quotient scores recorded during 3 subtests of the Sensory Organization Test (SOT), the number of falls during each subtest, the functional base of support, gait speed and cadence, single leg balance time, proximal strength, and vibrotactile threshold of the foot. The analysis employed the number of alcohol and drug abuse problems, depression severity, and body mass index as covariates. Results:ANCOVAs revealed significant decrements in the 3 HIV-1 seropositive groups relative to the control group on Equilibrium Quotient scores during the most difficult of the SOT subtests (sway-referenced support surface with eyes-closed). HIV/AIDS patients also exhibited a smaller functional base of support and greater vibrotactile thresholds. Antiretroviral treatment did not affect balance; but, it did alter sensory threshold in a complex manner. Conclusions:HIV/AIDS is associated with reliable decrements in balance and peripheral sensory function which are variably sensitive to antiretroviral treatment. The implications of these findings for mobility, and workplace or operator safety, should be contemplated.

Brain Maturation in Conduct Disorder versus Borderline Personality Disorder

Conduct disorder (CD) and borderline personality disorder (BPD) have been associated with abnormalities in brain function. The present study assessed whether adolescents with significant symptoms of CD and BPD display abnormal brain maturation. Participants recruited from the community were categorized as CD only, BPD only, CD plus BPD, or controls with neither CD nor BPD. Brain maturation was estimated by the amplitude difference in the P300 event-related brain potential between participants < versus ≧17 years old. With increasing age, controls and BPD only participants exhibited a P300 amplitude decline. This pattern was not evident in the CD only and CD plus BPD groups. The different brain maturation patterns seen in adolescents with CD versus BPD symptoms may contribute to differences in age-of-onset, clinical course, and resistance to treatment.