Identification of an Obese Eating Style in 4‐year‐old Children Born at High and Low Risk for Obesity

This study tested whether children's eating behavior and parental feeding prompts during a laboratory test meal differ among children born at high risk (HR) or low risk (LR) for obesity and are associated with excess child weight gain. At 4 years of age, 32 HR children (mean maternal prepregnancy BMI = 30.4 kg/m²) and 29 LR children (maternal BMI = 19.6 kg/m²) consumed a test meal in which their eating behavior was assessed, including rate of caloric consumption, mouthfuls/min, and requests for food. Parental prompts for the child to eat also were measured at year 4, and child body composition was measured at ages 4 and 6 years. T‐tests, and logistic and multiple regression analyses tested study aims. Results indicated that HR and LR children did not differ in eating rate or parental feeding prompts. Greater maternal BMI, child mouthfuls of food/min, and total caloric intake/min during the test meal predicted an increased risk of being overweight or obese at age 6, whereas greater active mealtime was associated with a reduced risk of being overweight or obese. Regression analyses indicated that only mouthfuls of food/min predicted changes in BMI from 4 to 6 years, and mouthfuls of food/min and gender predicted 2‐year changes in sum of skinfolds and total body fat. Thus, a rapid eating style, characterized by increased mouthfuls of food/min, may be a behavioral marker for the development of childhood obesity.     

The Role of Zinc and Iron-Folic Acid Supplementation on Early Child Temperament and Eating Behaviors in Rural Nepal: A Randomized Controlled Trial

Child eating behaviors play an important role in nutrient intake, ultimately affecting child growth and later outcomes in adulthood. The study assessed the effects of iron-folic acid and zinc supplementation on child temperament and child eating behaviors in rural Nepal. Children (N = 569) aged 4–17 months in Sarlahi district, southern Nepal were randomized to receive daily supplements of placebo, iron-folic acid, zinc, or zinc plus iron-folic acid and followed for approximately 1 year. At baseline and four follow-up visits mothers completed questionnaires including information on demographic characteristics and child temperament and eating behaviors. The main effects of zinc and iron-folic acid supplementation on temperament and eating behaviors were assessed through crude and adjusted differences in mean cumulative score changes between visits 1 and 5. The adjusted rate-of-change for these outcomes was modeled using generalized estimating equations. Mean changes in temperament scores and in eating behavior scores between visits 1 and 5 were not significant in either the zinc or non-zinc group. Children in the iron-folic acid group increased temperament scores by 0.37 points over 5 visits (95% CI 0.02, 0.7), which was not significant after adjustment. Neither the adjusted rate-of-change in temperament scores between zinc and non-zinc (β = −0.03, 95% CI −0.3, 0.2) or iron-folic acid and non-iron-folic acid (β = 0.08, 95% CI −0.2, 0.3) were significantly different. Adjusted rate of change analysis showed no significant difference between zinc and non-zinc (β = −0.14, 95% CI −0.3, 0.04) or between iron and non-iron eating behavior scores (β = −0.11, 95% CI −0.3, 0.1). Only among children with iron-deficiency anemia at baseline was there a significant decrease in eating behavior score, indicating better eating behaviors, when supplemented with zinc (β = −0.3, 95% CI −0.6, −0.01), Ultimately, this effect of zinc on eating behaviors was the only effect we observed after approximately one year of micronutrient supplementation.

Trial Registration

ClinicalTrials.gov NCT00109551     

When Chocolate Seeking Becomes Compulsion: Gene-Environment Interplay

Background

Eating disorders appear to be caused by a complex interaction between environmental and genetic factors, and compulsive eating in response to adverse circumstances characterizes many eating disorders.

Materials and Methods

We compared compulsion-like eating in the form of conditioned suppression of palatable food-seeking in adverse situations in stressed C57BL/6J and DBA/2J mice, two well-characterized inbred strains, to determine the influence of gene-environment interplay on this behavioral phenotype. Moreover, we tested the hypothesis that low accumbal D2 receptor (R) availability is a genetic risk factor of food compulsion-like behavior and that environmental conditions that induce compulsive eating alter D2R expression in the striatum. To this end, we measured D1R and D2R expression in the striatum and D1R, D2R and α1R levels in the medial prefrontal cortex, respectively, by western blot.

Results

Exposure to environmental conditions induces compulsion-like eating behavior, depending on genetic background. This behavioral pattern is linked to decreased availability of accumbal D2R. Moreover, exposure to certain environmental conditions upregulates D2R and downregulates α1R in the striatum and medial prefrontal cortex, respectively, of compulsive animals. These findings confirm the function of gene-environment interplay in the manifestation of compulsive eating and support the hypothesis that low accumbal D2R availability is a “constitutive” genetic risk factor for compulsion-like eating behavior. Finally, D2R upregulation and α1R downregulation in the striatum and medial prefrontal cortex, respectively, are potential neuroadaptive responses that parallel the shift from motivated to compulsive eating.     

The Evolving Genome Project: current and future impact.

The National Institutes of Health/Department of Energy Human Genome Project has been funding directed research for only 5 years, and it is understandably difficult to cite important research advances directly attributable to the project. However, the project has been constructive in fostering multidisciplinary group research and an inspiring and synergistic "just do it" attitude in both political and scientific circles, domestically and abroad. This collaborative spirit has spawned large-scale genetic and physical mapping projects, with the most impressive and useful results to date being the dense genetic maps produced by the Généthon, a French organization largely supported by the French muscular dystrophy association. With the genetic and physical map reagents now becoming available, disease-gene cloning is proceeding at an increasingly rapid pace. More important than the predictable acceleration of disease-gene mapping are the unpredictable benefits: Will a dense PCR-based dinucleotide-repeat genetic map open novel alternative approaches to disease-gene isolation? Will it become possible to localize disease genes by simply analyzing unrelated, isolated probands rather than the rarer "extended family"? Proband-based "linkage-disequilibrium cloning" may become possible if adequate density, informativeness, and stability of polymorphic loci are obtained. In addition, "genome exclusion cloning" will be added to the established positional, candidate-gene, and functional-disease-gene-cloning experimental approaches. The anticipated exponential expansion of human genetic disease information over the remainder of the 10-year tenure of the Human Genome Project unveils critical yet unresolved issues for medical education and the practice of medicine.(ABSTRACT TRUNCATED AT 250 WORDS)     

Part of my story. The meaning and experiences of genes and genetics for sperm donor-conceived offspring

Existing empirical research often do not explain which concepts about genetics underlie the assumption that genetic information is deemed important for donor-conceived offspring. This study focused on how donor-conceived individuals following anonymous sperm donation give meaning to and make sense of genes and genetics. Analysis is based on focus groups and interviews with adult donor-conceived offspring. Findings suggest that genes are part of their specific context of being donor-conceived but also play a role in daily life. Genes make sense on an individual level and a relational level, both on parent-child as sibling-level. On an individual level they were perceived as (1) a biological starting package, (2) their own unique combination and (3) as a reference point. On a relational level, genes were seen as (1) “person-al”, (2) connecting and (3) locating individuals. This information is essential for those supporting/counseling donor conceived offspring and families as well as for policy-members.     

Intergenerational transmission of dietary habits among Italian children and adolescents

The aim of this paper is to investigate the relationship between parental dietary habits and child and adolescent diet quality in Italy by adopting a parent-child perspective. We apply quantile regression modelling to an original database developed within the DEDIPAC knowledge hub, integrating multiple sources of information on the aspects of Italian households’ daily lives, food consumption frequency, and calorie intake. Given the relevance of maternal care in shaping children’s eating patterns, we focus on mothers’ lifestyles and time-use. Results show that the intergenerational transmission of diet quality is a gendered process, especially involving mothers and their daughters. Our findings also highlight the pivotal role schools play in the fight against child malnutrition and indicate that, contrary to what is found in the international research literature, maternal employment is not correlated with a deterioration in their children’s diet quality.     

Effect of lactation trimester and parity on eating behavior,milk production and efficiency traits of dairy cows

There is absence knowledge about the effects of lactation trimester and parity on eating behavior, production and efficiency of dairy cows. Objective of this study was to identify and characterize in 340 dairy cows, the 20% high efficient (HE), 20% low efficient (LE) and 60% mid efficient (ME) cows according to their individual residual feed intake (RFI) values, within and between lactation trimesters and between 1st and 2nd parities. Efficiency effect within each lactation trimester, was exhibited in daily dry matter intake (DMI), eating rate and meal size, that were the highest in LE cows, moderate in the ME cows and lowest in the HE group. Daily eating time, meal frequency, yields of milk and energy-corrected milk (ECM) and BW were similar in the three efficiency groups within each trimester. The lower efficiency of the LE cows in each trimester attributes to their larger metabolic energy intake, heat production and energy losses. In subgroup of 52 multiparous cows examined along their 1st and 2nd trimesters, milk and ECM production, DMI, eating behavior and efficiency traits were similar with high Pearson’s correlation (r=0.78 to 0.89) between trimesters. In another subgroup of 42 multiparous cows measured at their 2nd and 3rd trimesters, milk and ECM yield, DMI and eating time were reduced (P<0.01) at the 3rd trimester, but eating rate, meal frequency and meal size remained similar with high Pearson’s correlation (r=0.74 to 0.88) between trimesters. In subgroup of 26 cows measured in 1st and 2nd parities, DMI, BW, milk and ECM yield, and ECM/DMI increased in the 2nd lactation, but eating behavior and RFI traits were similar in both parities. These findings encourage accurate prediction of DMI based on a model that includes eating behavior parameters, together with individual measurement of ECM production. This can be further used to identify HE cows in commercial herd, a step necessary for potential genetic selection program aimed to improve herd efficiency.     

TAS2R38 and Its Influence on Smoking Behavior and Glucose Homeostasis in the German Sorbs

Background

Genetic variants within the bitter taste receptor gene TAS2R38 are associated with sensitivity to bitter taste and are related to eating behavior in the Amish population. Sensitivity to bitter taste is further related to anthropometric traits in an genetically isolated Italian population. We tested whether the TAS2R38 variants (rs713598; rs1726866 and rs10246939) may be related to eating behavior, anthropometric parameters, metabolic traits and consumer goods intake in the German Sorbs.

Materials and Methods

The three SNPs were genotyped in a total cohort of 1007 individuals (male/female: 405/602). The German version of the three-factor eating questionnaire was completed by 548 individuals. Genetic association analyses for smoking behavior, alcohol and coffee intake, eating behavior factors (restraint, disinhibition and hunger) and other metabolic traits were analyzed. Further, by combining the three SNPs we applied comparative haplotype analyses categorizing PAV (proline-alanine-valine) carriers (tasters) vs. homozygous AVI (alanin-valine-isoleucine) carriers (non-tasters).

Results

Significant associations of genetic variants within TAS2R38 were identified with percentage of body fat, which were driven by associations in women. In men, we observed significant associations with 30 min plasma glucose, and area under the curve for plasma glucose (0–120 min) (all adjusted P≤0.05). Further, we found that carriers of at least one PAV allele show significantly lower cigarette smoking per day (P = 0.002) as well as, albeit non-significant, lower alcohol intake. We did not confirm previously reported associations between genetic variants of TAS2R38 and eating behavior.

Conclusion

Our data suggest that genetic variation in TAS2R38 is related to individual body composition measures and may further influence consumer goods intake in the Sorbs possibly via individual sensitivity to bitter taste.     

Parent‐Child Feeding Strategies and Their Relationships to Child Eating and Weight Status

Parental feeding styles may promote overeating or overweight in children. A comprehensive literature review was undertaken to summarize the associations between parental feeding styles and child eating and weight status. Twenty‐two studies were identified. We systematically coded study attributes and outcomes and tested for patterns of association. Nineteen studies (86%) reported at least one significant association between parental feeding style and child outcome, although study methodology and results varied considerably. Studies measuring parental feeding restriction, as opposed to general feeding control or another feeding domain, were more likely to report positive associations with child eating and weight status. Certain associations differed by gender and by outcome measurement (e.g., rate of eating as opposed to total energy intake). Parental feeding restriction, but no other feeding domain, was associated with increased child eating and weight status. Longitudinal studies are needed to test underlying causal pathways, including bidirectional causal models, and to substantiate findings in the presence of other obesity risk factors.     

Association of the melanocortin 4 receptor gene rs17782313 polymorphism with rewarding value of food and eating behavior in Chilean children

Studies conducted in monozygotic and dizygotic twins have established a strong genetic component in eating behavior. Rare mutations and common variants of the melanocortin 4 receptor (MC4R) gene have been linked to obesity and eating behavior scores. However, few studies have assessed common variants in MC4R gene with the rewarding value of food in children. The objective of the study was to evaluate the association between the MC4R rs17782313 polymorphism with homeostatic and non-homeostatic eating behavior patterns in Chileans children. This is a cross-sectional study in 258 Chilean children (44 % female, 8–14 years old) showing a wide variation in BMI. Anthropometric measurements (weight, height, Z-score of BMI and waist circumference) were performed by standard procedures. Eating behavior was assessed using the Eating in Absence of Hunger Questionnaire (EAHQ), the Child Eating Behavior Questionnaire (CEBQ), the Three-Factor Eating Questionnaire (TFEQ), and the Food Reinforcement Value Questionnaire (FRVQ). Genotype of the rs17782313 nearby MC4R was determined by a Taqman assay. Association of the rs17782313 C allele with eating behavior was assessed using non-parametric tests. We found that children carrying the CC genotype have higher scores of food responsiveness (p value = 0.02). In obese girls, carriers of the C allele showed lower scores of satiety responsiveness (p value = 0.02) and higher scores of uncontrolled eating (p value = 0.01). Obese boys carrying the C allele showed lower rewarding value of food in relation to non-carriers. The rs17782313 C allele is associated with eating behavior traits that may predispose obese children to increased energy intake and obesity.     

An embedded longitudinal multi-faceted qualitative evaluation of a complex cluster randomized controlled trial aiming to reduce clinically important errors in medicines management in general practice

Background

Children who witness interparental violence are at a heightened risk for developing psychosocial, behavioral and cognitive problems, as well as posttraumatic stress symptoms. For these children the psycho-educational secondary prevention program 'En nu ik...!' ('It's my turn now!') has been developed. This program includes specific therapeutic factors focused on emotion awareness and expression, increasing feelings of emotional security, teaching specific coping strategies, developing a trauma narrative, improving parent-child interaction and psycho-education. The main study aim is to evaluate the effectiveness of the specific therapeutic factors in the program. A secondary objective is to study mediating and moderating factors.

Methods/design

This study is a prospective multicenter randomized controlled trial across cities in the Netherlands. Participants (N = 140) are referred to the secondary preventive intervention program by police, social work, women shelters and youth (mental health) care. Children, aged 6-12 years, and their parents, who experienced interparental violence are randomly assigned to either the intervention program or the control program. The control program is comparable on nonspecific factors by offering positive attention, positive expectations, recreation, distraction, warmth and empathy of the therapist, and social support among group participants, in ways that are similar to the intervention program. Primary outcome measures are posttraumatic stress symptoms and emotional and behavioral problems of the child. Mediators tested are the ability to differentiate and express emotions, emotional security, coping strategies, feelings of guilt and parent-child interaction. Mental health of the parent, parenting stress, disturbances in parent-child attachment, duration and severity of the domestic violence and demographics are examined for their moderating effect. Data are collected one week before the program starts (T1), and one week (T2) and six months (T3) after finishing the program. Both intention-to-treat and completer analyses will be done.

Discussion

Adverse outcomes after witnessing interparental violence are highly diverse and may be explained by multiple risk factors. An important question for prevention programs is therefore to what extent a specific focus on potential psychotrauma is useful. This trial may point to several directions for optimizing public health response to children's exposure to interparental violence.

Trial registration

Netherlands Trial Register (NTR): NTR3064     

Eating With Your Favourite Mother: Time And Sociality In A Brazilian Amerindian Community

This article is based on an ethnographic account of parent-child relations in a Caboclo-Indian community of south Bahia, Brazil. Raising a child by providing care and food is valued to such an extent that a child's mother may be the woman the child has chosen to be its mother. Choice is not understood as an act of free will, but as a time-frame in the sense that choosing one's mother is a way of emphasizing the possibility of the unmaking or reversibility of parent-child links. The article suggests a 'sociality of becoming a being-in-the-world' as an alternative not only to the notion of socialization but also to the theoretical link between kinship and society.

The Kid has changed the world and myself. Not in the beginning But bit by bit, As I became attached to him Andrei Tarkovskij, The sacrifice

     

Parent-only treatment for childhood obesity: a randomized controlled trial

Parent-only (PO) treatments for childhood obesity are feasible, more cost-effective and potentially easier to disseminate. The objective of this study was to determine whether a PO treatment is not inferior to a parent + child (PC) treatment for childhood obesity. Eighty parent-child dyads with an 8-12 year old overweight or obese child (>85th BMI-P) were recruited and randomized into PO or PC treatment for childhood obesity. Parents or parent-child dyads attended 5-month treatment groups. Child and parent body size, child caloric intake, and child physical activity were assessed at baseline, post-treatment, and 6-months follow-up. Noninferiority testing using mixed linear models was used to compare PO treatment with PC treatment. Results showed that the PO group was not inferior to the PC group in terms of child weight loss. Results also showed that the PO group was not inferior to the PC group in terms of parent weight loss and child physical activity, but not child caloric intake. This study suggests that a PO treatment could provide similar results to PC in child weight loss and other relevant outcomes, and potentially could be more cost-effective and easier to disseminate. Although further research is needed, this study suggests that PO groups are a viable method for providing childhood obesity treatment.     

Classification of feeding and eating disorders: review of evidence and proposals for ICD-11

Current classification of eating disorders is failing to classify most clinical presentations; ignores continuities between child, adolescent and adult manifestations; and requires frequent changes of diagnosis to accommodate the natural course of these disorders. The classification is divorced from clinical practice, and investigators of clinical trials have felt compelled to introduce unsystematic modifications. Classification of feeding and eating disorders in ICD-11 requires substantial changes to remediate the shortcomings. We review evidence on the developmental and cross-cultural differences and continuities, course and distinctive features of feeding and eating disorders. We make the following recommendations: a) feeding and eating disorders should be merged into a single grouping with categories applicable across age groups; b) the category of anorexia nervosa should be broadened through dropping the requirement for amenorrhoea, extending the weight criterion to any significant underweight, and extending the cognitive criterion to include developmentally and culturally relevant presentations; c) a severity qualifier "with dangerously low body weight" should distinguish the severe cases of anorexia nervosa that carry the riskiest prognosis; d) bulimia nervosa should be extended to include subjective binge eating; e) binge eating disorder should be included as a specific category defined by subjective or objective binge eating in the absence of regular compensatory behaviour; f) combined eating disorder should classify subjects who sequentially or concurrently fulfil criteria for both anorexia and bulimia nervosa; g) avoidant/restrictive food intake disorder should classify restricted food intake in children or adults that is not accompanied by body weight and shape related psychopathology; h) a uniform minimum duration criterion of four weeks should apply.     

Genome-Wide Association Study Reveals Genetic Architecture of Eating Behavior in Pigs and Its Implications for Humans Obesity by Comparative Mapping

This study was aimed at identifying genomic regions controlling feeding behavior in Danish Duroc boars and its potential implications for eating behavior in humans. Data regarding individual daily feed intake (DFI), total daily time spent in feeder (TPD), number of daily visits to feeder (NVD), average duration of each visit (TPV), mean feed intake per visit (FPV) and mean feed intake rate (FR) were available for 1130 boars. All boars were genotyped using the Illumina Porcine SNP60 BeadChip. The association analyses were performed using the GenABEL package in the R program. Sixteen SNPs were found to have moderate genome-wide significance (p<5E-05) and 76 SNPs had suggestive (p<5E-04) association with feeding behavior traits. MSI2 gene on chromosome (SSC) 14 was very strongly associated with NVD. Thirty-six SNPs were located in genome regions where QTLs have previously been reported for behavior and/or feed intake traits in pigs. The regions: 64–65 Mb on SSC 1, 124–130 Mb on SSC 8, 63–68 Mb on SSC 11, 32–39 Mb and 59–60 Mb on SSC 12 harbored several signifcant SNPs. Synapse genes (GABRR2, PPP1R9B, SYT1, GABRR1, CADPS2, DLGAP2 and GOPC), dephosphorylation genes (PPM1E, DAPP1, PTPN18, PTPRZ1, PTPN4, MTMR4 and RNGTT) and positive regulation of peptide secretion genes (GHRH, NNAT and TCF7L2) were highly significantly associated with feeding behavior traits. This is the first GWAS to identify genetic variants and biological mechanisms for eating behavior in pigs and these results are important for genetic improvement of pig feed efficiency. We have also conducted pig-human comparative gene mapping to reveal key genomic regions and/or genes on the human genome that may influence eating behavior in human beings and consequently affect the development of obesity and metabolic syndrome. This is the first translational genomics study of its kind to report potential candidate genes for eating behavior in humans.     

Genetic fatalism and social policy: the implications of behavior genetics research.

Recent advances in molecular genetics methods have provided new means of determining the genetic bases of human behavioral traits. The impetus for the use of these approaches for specific behaviors depends, in large part, on previous familial studies on inheritance of such traits. In the past, a finding of a genetic basis for a trait was often accompanied with the idea that that trait is unchangeable. We discuss the definition of "genetic trait" and heritability and examine the relationship between these concepts and the malleability of traits for both molecular and nonmolecular approaches to behavioral genetics. We argue that the malleability of traits is as much a social and political question as it is a biological one and that whether or not a trait is genetic has little relevance to questions concerning determinism, free will, and individual responsibility for actions. We conclude by noting that "scientific objectivity" should not be used to conceal the social perspectives that underlie proposals regarding social change.     

Pramlintide treatment reduces 24-h caloric intake and meal sizes and improves control of eating in obese subjects: a 6-wk translational research study

Evidence from rodent studies indicates that the beta-cell-derived neurohormone amylin exerts multiple effects on eating behavior, including reductions in meal size, intake of highly palatable foods, and stress-induced sucrose consumption. To assess the effect of amylin agonism on human eating behavior we conducted a randomized, blinded, placebo-controlled, multicenter study investigating the effects of the amylin analog pramlintide on body weight, 24-h caloric intake, portion sizes, "fast food" intake, and perceived control of eating in 88 obese subjects. After a 2-day placebo lead-in, subjects self-administered pramlintide (180 microg) or placebo by subcutaneous injection 15 min before meals for 6 wk without concomitant lifestyle modifications. Compared with placebo, pramlintide treatment elicited significant mean reductions from baseline in body weight on day 44 (-2.1 +/- 0.3 vs. +0.1 +/- 0.4%, P < 0.001), 24-h caloric intake (-990 +/- 94 vs. -243 +/- 126 kcal on day 3, P < 0.0001; -680 +/- 86 vs. -191 +/- 161 kcal on day 43, P < 0.01), portion sizes, and caloric intake at a "fast food challenge" (-385 +/- 61 vs. -109 +/- 88 kcal on day 44, P < 0.05). Pramlintide treatment also improved perceived control of eating, as demonstrated by a 45% placebo-corrected reduction in binge eating scores (P < 0.01). The results of this translational research study confirm in humans various preclinical effects of amylin agonism, demonstrating that pramlintide-mediated weight loss in obese subjects is accompanied by sustained reductions in 24-h food intake, portion sizes, fast food intake, and binge eating tendencies.     

Effect of management of patients with Anorexia and Bulimia nervosa on symptoms and impulsive behavior

The aim of the study was to provide further and up to date information on the evaluation of the management of Anorexia and Bulimia nervosa at the Eating Disorders Unit (EDU) of the Ljubljana Psychiatric Clinic, based upon detailed assessment of the eating disorders specific and non specific symptoms of impulsive behaviors, highly correlated with these entities. 34 female patients with anorexia (restrictive or purgative type) and 38 female patients with Bulimia nervosa (purgative or non-purgative type) undergoing hospital treatment at the EDU were evaluated upon admission, as well as upon discharge and three and six months after discharge, using the Eating Disorder Questionnaire. Upon discharge a marked decrease in the overall symptoms was noted. The differences in symptoms incidences between the two groups were significantly specific for the individual form of eating disorder, especially upon admission, and were more pronounced in anorexia group. In later measurements, performed during the period of three and six months after discharge, a mild trend of increase in the disorder specific symptoms was detected in both groups, but was not statistically significant. In addition to binging on food, striking, quarreling and spending sprees are characteristics of patients with eating disorders, which in particular apply to the Bulimia nervosa group. Apart from the disorder specific symptoms, impulsive behavior was also reduced during study period, while the difference in its occurrence between the two groups gradually became non-significant. The management of patients with eating disorders at the EDU was successful in both groups, confirmed by an intense reduction of the disorder specific symptoms, impulsive behavior and increased stability recorded three and six months after discharge. The study strongly suggests that the effect of treatment regime for eating disorders can be predicted by careful assessment of the relevant symptoms and impulsive behavioral patterns.     

Optical and genetic approaches toward understanding neuronal circuits in zebrafish

Optical and genetic tools are beginning to revolutionize thestudies of neuronal circuits. Neurons can now be labeled withconventional or genetically encoded indicators that allow theiractivity to be monitored during behavior in intact animals.Laser ablations and genetic inactivation offer ways to perturbactivity of specific cells to test their contributions to behavior.These approaches promise to speed progress in the understandingof vertebrate networks in genetic model systems such as miceand zebrafish. Here we review some of the progress in applyingthese tools, with an emphasis on our work to develop and applythese approaches in the zebrafish model.