***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The possible differences in processing gustatory stimuli in anorexic patients compared to healthy control subjects was investigated by electrophysiological methods . The  electroencephalogram ( EEG )  was recorded in out patients treated with anorexia nervosa ( AN ) and age-matched controls after exposure to sweet ( milk chocolate ) and bitter ( black tea ) taste stimuli . Power spectrum analysis was performed on EEG epochs recorded in the above conditions . Compared to controls a significantly higher percent of theta , and lower percent of alpha1 b and power was found in anorexic patients , irrespective of the kind of taste effects and hemispheric side . The pattern of activation caused by sweet and bitter stimuli was found to be different in these two groups , possibly indicating altered gustatory processing mechanisms in AN We evaluated the changes in taste responsiveness of anorexia nervosa ( AN ) patients during behavior therapy .  Taste responsiveness of AN patients was lower at admission when compared to controls but it improved significantly over the course of treatment ( p < 0.01 ) . Taste responsiveness improved prior to increase in body weight . No significant correlation was noted between weight gain and improvement in taste responsiveness . The period required to reach a food intake of 1600 Kcal/day and the duration of hospitalization were highly correlated ( r = 0.72 , p < 0.05 ) . Those who reached 1600 Kcal/day earlier showed more rapid improvements in taste responsiveness . These results suggest that decreased taste responsiveness in AN patients can rapidly improve and such early improvement may result in better progression of treatment Restrictive eating disorders ( ED ) are increasing and represent a serious risk to the health of adolescent females . Restrictive ED in youth are often treated through aggressive short-term refeeding . Although evidence supports that this intervention is the " gold st and ard " for improving ED outcomes in youth , little research has specifically probed appetite and meal-related responses to this type of intensive , short-term refeeding in newly diagnosed individuals . Information about appetite and meal-related dysfunction could provide valuable insights regarding treatment-interfering features of ED in both acute inpatient and longer-term outpatient treatment . The purpose of this study was to evaluate the hunger , fullness , olfactory , and gustatory responses of adolescents with newly-diagnosed restrictive ED and to probe how and when these responses are altered by refeeding . Using a quasi-experimental ecologically valid methodology , this study described and compared profiles of hunger , fullness , olfactory , and gustatory responses in adolescent females ( n = 15 ) with newly diagnosed restrictive ED at hospital admission ( i.e. , severe malnutrition ) and after medical refeeding  , in comparison to healthy controls ( n = 15 ) . Results showed that newly diagnosed ( i.e. , malnourished ) adolescents with ED showed significantly different meal-related experiences than controls . Refeeding improved some of these differences , but not all . Following refeeding , females with ED continued to show lower hunger , greater fullness , and lower pleasantness of smell ratings compared to controls . Unpleasantness of taste ratings maladaptively increased , such that females who were re-fed reported more aversive scents than pre-treatment . Profiles of meal-related responses were also identified and compared between groups . The applicability of these findings are discussed within the context of critical periods of change during refeeding treatment and potentially promising intervention targets that might enhance treatment outcomes for adolescents with newly onset , restrictive ED Taste responses to sucrose and fat-containing stimuli were examined in a population of young women with eating disorders . Anorectic-restrictor and anorectic-bulimic patients were compared with normal-weight bulimic patients and with normal-weight control subjects .  Sensory estimates of sweetness and fat content of 20 different mixtures of milk , cream , and sugar did not differ among subject groups . In contrast , relative preferences for sugar vs fat as determined by the Response Surface Method differed between patients with eating disorders and control subjects . Normal-weight bulimic patients preferred sweeter stimuli than did control subjects . Anorectic-restrictor and anorectic-bulimic patients liked sweet but disliked high-fat stimuli and showed elevated optimal sugar : fat ( S : F ) ratios . This pattern of response did not change following weight regain . The stability of preference profiles suggests that taste responsiveness may be independent of diagnostic categories , bulimic behaviors , or acute changes in body weight To test the hypothesis that endogenous opiate peptides selectively influence hedonic response to sweet and high-fat foods , the opiate antagonist naloxone , opiate agonist butorphanol , and a saline placebo were administered by intravenous infusion to 16 obese and 25 normal-weight women . Twenty of the women ( 10 obese , 10 lean ) fulfilled DSM-III-R diagnostic criteria for bulimia nervosa , as determined by psychiatric interview . During drug infusion the women tasted and rated 20 sweetened dairy products and were presented with eight snack foods of varying sugar and fat content . Naloxone suppressed hedonic responses in all subject groups and suppressed the consumption of sweet and high-fat foods in binge eaters , but not in nonbingers . Food intakes of obese women were not affected by naloxone . Butorphanol had no effect on either hedonic response or on food consumption in any group . Although opiate blockade is not a viable strategy for weight reduction in the treatment of obesity , it may be useful in the clinical management of the binge-eating disorder The aim of this study was to identify cortical areas important for optimal cognitive aging .  74 participants ( 20 - 88 years ) went through neuropsychological tests and two MR sessions . The sample was split into two age groups . In each , every participant was classified as " high " or " average " on  fluid ability tests and on  neuropsychological tests related to executive function . The groups were compared with regard to thickness on a point-by-point basis across the entire cortical mantle . The old high fluid performers had thicker cortex than the average performers in large areas of cortex , while there was minimal difference between the groups of high vs. average executive function . Furthermore , the old group with high fluid function had thicker cortex than the young participants in the posterior cingulate and adjacent areas . Further analyses showed that the latter was a result of a complex aging pattern , differing between the two performance groups , with decades of cortical thickening and subsequent thinning Binge eating is often preceded by reports of negative affect , but the mechanism by which affect may lead to binge eating is unclear . This study evaluated the effect of negative affect on neural response to anticipation and receipt of palatable food in women with bulimia nervosa ( BN ) versus healthy controls . We also evaluated connectivity between the amygdala and reward-related brain regions . Females with and without BN ( n=26 ) underwent functional magnetic resonance imaging ( fMRI ) during receipt and anticipated receipt of chocolate milkshake and a tasteless solution . We measured negative affect just prior to the scan . Women with BN showed a positive correlation between negative affect and activity in the putamen , cau date , and pallidum during anticipated receipt of milkshake ( versus tasteless solution ) . There were no significant relations between negative affect and receipt of milkshake . Connectivity analyses revealed a greater relation of amygdala activity to activation in the left putamen and insula during anticipated receipt of milkshake in the bulimia group relative to the control group . The opposite pattern was found for the taste of milkshake ; the control group showed a greater relation of amygdala activity to activation in the left putamen and insula in response to milkshake receipt than the bulimia group . Results show that as negative affect increases , so does responsivity of reward regions to anticipated intake of palatable food , implying that negative affect may increase the reward value of food for individuals with bulimia nervosa or that negative affect has become a conditioned cue due to a history of binge eating in a negative mood Preferences and cravings for sweet high-fat foods observed among obese and bulimic patients may involve the endogenous opioid peptide system . The opioid antagonist naloxone , opioid agonist butorphanol , and saline placebo were administered by intravenous infusion to 14 female binge eaters and 12 normal-weight controls . Eight of the binge eaters were obese . During infusion , the subjects tasted 20 sugar/fat mixtures and were allowed to select and consume snack foods of varying sugar and fat content . Naloxone reduced taste preferences relative to baseline in both binge eaters and controls . Total caloric intake from snacks was significantly reduced by naloxone in binge eaters but not in controls . This reduction was most pronounced for sweet high-fat foods such as cookies or chocolate . No consistent effects on taste preferences or food intakes were observed with butorphanol . Endogenous opioid peptides may be involved in mediating taste responses and preferences for palatable foods , notably those rich in sugar and fat OBJECTIVE Most previous studies of the prevalence , incidence , and outcome of anorexia nervosa have been limited to cases detected through the health care system , which may bias our underst and ing of the disorder 's incidence and natural course . The authors sought to describe the onset and outcomes of anorexia nervosa in the general population . METHOD Lifetime prevalences , incidence rates , and 5-year recovery rates of anorexia nervosa were calculated on the basis of data from 2,881 women from the 1975 - 1979 birth cohorts of Finnish twins . Women who screened positive for eating disorder symptoms ( N=292 ) , their screen-negative female co-twins ( N=134 ) , and 210 r and omly selected screen-negative women were assessed for lifetime eating disorders by telephone by experienced clinicians . To assess outcomes after clinical recovery and to detect residua of illness , women who had recovered were compared with their unaffected co-twins and healthy unrelated women on multiple outcome measures . RESULTS The lifetime prevalence of DSM-IV anorexia nervosa was 2.2 % , and half of the cases had not been detected in the health care system . The  incidence of anorexia nervosa in women between 15 and 19 years of age was 270 per 100,000 person-years . The 5-year clinical recovery rate was 66.8 % . Outcomes did not differ between detected and undetected cases . After clinical recovery , the residua of illness steadily receded . By 5 years after clinical recovery , most prob and s had reached complete or nearly complete psychological recovery and closely resembled their unaffected co-twins and healthy women in weight and most psychological and social measures . CONCLUSIONS The authors found a substantially higher lifetime prevalence and incidence of anorexia nervosa than reported in previous studies , most of which were based on treated cases . Most women recovered clinical ly within 5 years , and thereafter usually progressed toward full recovery Previous research has shown that patients with bulimia nervosa ( B ) , anorexia nervosa , restricting type , or restrictive-anorectic ( RA ) , and anorexia nervosa , binge eating , purging type , or anorectic-bulimic ( AB ) exhibit a reduced hedonic response to sucrose compared with control subjects . We hypothesized that this response could be linked to an excessive fear of weight gain rather than a decreased ability to experience pleasure . We therefore compared the hedonic responses to sucrose solutions in B , RA and AB women ( n=20/group ) in two different conditions : sucrose solution swallowed vs. sucrose solution spit . Under double-blind conditions and according to a Latin square design , patients received sucrose in solution ( 0 , 5 , 10 , 20 , and 40 % ) and rated each concentration for pleasantness on a nine-point scale . The two test conditions were r and omly administered . The threshold concentration of sweet taste perception was also assessed , and the subjects filled out Chapman 's Social and Physical Anhedonia Scale . The hedonic response to sucrose adjusted for the sweet taste perception threshold was significantly lower in the ' swallow ' than in the ' spit ' condition . There was a significant effect of sucrose concentrations as well as a significant condition by concentration interaction . When ' fear to swallow ' sucrose solution responses were included as a covariate , the significant difference between the conditions of ' swallow ' or ' spit ' disappeared , but there was a significant concentration by condition by fear to swallow interaction and an almost significant covariate effect . When ' Drive for Thinness ' on the Eating Disorder Inventory was included as a covariate , similar results were obtained . Social Anhedonia but not Physical Anhedonia correlated positively with ' Drive for Thinness ' and ' fear of swallowing sucrose solutions ' , and correlated inversely with maximal hedonic response to the ' swallow ' condition . ' We conclude that the hedonic responses to sucrose in patients with eating disorders are decreased when solutions are swallowed . This may reflect excessive fear of gaining weight rather than decreased ability to experience pleasure ' The overall aim of the present study was to investigate a new method for the screening of taste function in a clinical context . Instead of dripping liquids onto the tongue , thin edible wavers were used . One-hundred healthy subjects participated in the study ( 41 male , 59 female ; mean age : 52 years ; age range : 20 - 89 years ) . Supra-threshold taste stimuli were presented as flavoured wavers made from flour and water . Sequential testing was performed regionally on the anterior one-third of the tongue and as whole mouth testing . When comparing ratings for the 5 different wavers separately for regional and whole mouth testing , differences between qualities only emerged for regional testing . Women were found to have less difficulty in taste identification which was most pronounced for regional testing . No effects of the subjects ' age were observed . In conclusion , the wavers were found to be easy to use ; they have a shelf-life of 2 to 3 years and can be carried in the pocket . The results indicate that the wavers may be suited for the screening of gustatory function , especially in a clinical setting Although it is possible that binge eating in humans is due to increased responsiveness of orosensory excitatory controls of eating , there is no direct evidence for this because food 
    Output:
    
Psychophysical studies showed that individuals with BN , in general , had greater preference for sweetness than healthy controls , and those with AN had a greater aversion for fat than controls .
In neuroimaging studies , findings suggested that predictable administration of sweet-taste stimuli was associated with reduced activation in taste-reward regions of the brain among individuals with AN ( e.g. , insula , ventral , and dorsal striatum ) but increased activation in BN and BED .
Discussion : To our knowledge , this systematic review is the first to synthesize literature on taste differences in AN , BN , and BED .