A narrative review of the construct of hedonic hunger and its measurement by the Power of Food Scale.

INTRODUCTION: The term 'hedonic hunger' refers to one's preoccupation with and desire to consume foods for the purposes of pleasure and in the absence of physical hunger. The Power of Food Scale (PFS) was developed as a quantitative measure of this construct in 2009. Since then, over 50 published studies have used the PFS to predict appetite-related outcomes including neural, cognitive, behavioural, anthropometric and clinical measures. OBJECTIVE: This narrative review evaluates how closely the PFS captures the construct it was originally presumed to assess and to more clearly define hedonic hunger itself. METHODS: The measure's relationship to four domains is reviewed and summarized: motivation to consume palatable foods; level of actual consumption of such foods; body mass; and subjective loss-of-control over one's eating behaviour. Findings are synthesized to generate a more accurate understanding of what the PFS measures and how it may relate to the broader definition of hedonic hunger. RESULTS: Results suggest that the PFS is closely related to motivation to consume palatable foods and, in extreme cases, occurrence of loss-of-control eating episodes. PFS scores are not consistently predictive of amount of food consumed or body mass. CONCLUSIONS: Implications of these findings are discussed in the context of behavioural health, and avenues for further inquiry are identified.

The relation of hedonic hunger and restrained eating to lateralized frontal activation.

Asymmetrical alpha activation in the prefrontal cortex (frontal asymmetry) in electroencephalography (EEG) has been related to eating behavior. Prior studies linked dietary restraint with right frontal asymmetry [1] and disinhibition with left frontal asymmetry [2]. The current study simultaneously assessed restrained eating and hedonic hunger (drive for food reward in the absence of hunger) in relation to frontal asymmetry. Resting-state EEG and measures of restrained eating (Revised Restraint Scale; RRS) and hedonic hunger (Power of Food Scale; PFS) were assessed in 61 non-obese adults. Individually, hedonic hunger predicted left asymmetry. However, PFS and RRS were correlated (r=0.48, p<0.05) and there was a significant interaction between PFS and RRS on frontal asymmetry, p<0.01. Results indicated that those high in hedonic hunger exhibited left asymmetry irrespective of RRS scores; among those low in PFS, only those high in RRS showed right asymmetry. Results were consistent with literature linking avoidant behaviors (restraint) with right-frontal asymmetry and approach behaviors (binge eating) with left-frontal asymmetry. It appears that a strong drive toward palatable foods predominates at a neural level even when restraint is high. Findings suggest that lateralized frontal activity is an indicator of motivation both to consume and to avoid consuming highly palatable foods.

Personal history of dieting and family history of obesity are unrelated: implications for understanding weight gain proneness.

Identifying predictors of future weight gain is important in obesity prevention efforts. Both family history of obesity and personal dieting history have been established as predictors of future weight gain; however, it is unknown if they are independent or overlapping predictors. The purpose of this study was to examine the degree of overlap between these two predictors using cross-sectional data. Baseline data from four studies were examined separately and in combination for a total of 561 female participants, and analyses were conducted to examine parent anthropometric variables by dieting status within and across studies. All participants were female university students between the ages of 17 and 30. For each study, as well as for the entire sample combined, parent anthropometric variables were examined by dieting status using factorial ANOVAs. No meaningful pattern was found when examining parent anthropometric variables by dieting status, which suggests that the two risk factors are largely independent. This suggests that the processes associated with the development of future weight gain by each variable are different; therefore, future research should use a longitudinal study to test the hypothesis that using both variables to predict future weight gain would account for more variance than using either variable alone.

Dieting: proxy or cause of future weight gain?

The relationship between dieting and body mass has a long and controversial history. This paper aims to help resolve this issue by making two key distinctions. The first is between dieting as a cause of weight gain/regain and as a proxy risk factor for identifying non-obese individuals prone to weight gain for reasons other than dieting. The second is between the body mass that is attained following one or more weight loss/regain cycles and the body mass that might have been reached had dieting never been undertaken. Evidence is reviewed on the relation between recent diet-induced weight loss and sustained weight loss (weight suppression), on the one hand, and weight regain, on the other hand. Furthermore, the reason that a history of dieting in non-obese individuals reflects a susceptibility to future weight gain is explained. It is concluded that (i) diet-induced weight loss hastens weight regain but a history of weight loss diets does not cause weight gain beyond that which would occur in the absence of dieting, and (ii) weight loss dieting in non-obese individuals does not cause future weight gain but is simply a proxy risk factor reflecting a personal vulnerability to weight gain and living in an obesogenic environment.

The mind your health project: a randomized controlled trial of an innovative behavioral treatment for obesity.

OBJECTIVE: To determine whether acceptance-based behavioral treatment (ABT) would result in greater weight loss than standard behavioral treatment (SBT), and whether treatment effects were moderated by interventionist expertise or participants' susceptibility to eating cues. Recent research suggests that poor long-term weight-control outcomes are due to lapses in adherence to weight-control behaviors and that adherence might be improved by enhancing SBT with acceptance-based behavioral strategies. DESIGN AND METHODS: Overweight participants (n = 128) were randomly assigned to 40 weeks of SBT or ABT. RESULTS: Both groups produced significant weight loss, and when administered by experts, weight loss was significantly higher in ABT than SBT at post-treatment (13.17% vs. 7.54%) and 6-month follow-up (10.98% vs. 4.83%). Moreover, 64% of those receiving ABT from experts (vs. 46% for SBT) maintained at least a 10% weight loss by follow-up. Moderation analyses revealed a powerful advantage, at follow-up, of ABT over SBT in those potentially more susceptible to eating cues. For participants with greater baseline depression symptomology, weight loss at follow-up was 11.18% in ABT versus 4.63% in SBT; other comparisons were 10.51% versus 6.00% (emotional eating), 8.29% versus 6.35% (disinhibition), and 9.70% versus 4.46% (responsivity to food cues). Mediation analyses produced partial support for theorized food-related psychological acceptance as a mechanism of action. CONCLUSIONS: Results offer strong support for the incorporation of acceptance-based skills into behavioral weight loss treatments, particularly among those with greater levels of depression, responsivity to the food environment, disinhibition, and emotional eating, and especially when interventions are provided by weight-control experts.

Self-reported history of overweight and its relationship to disordered eating in adolescent girls with Type 1 diabetes.

AIMS: Increased body weight and disordered eating attitudes/behaviours are common in adolescent girls with Type 1 diabetes (T1D). Disordered eating increases risks for diabetes-related complications. This study aimed to identify a rapid screening approach for disordered eating attitudes and behaviours in adolescent girls with T1D and to examine the relationship between disordered eating and body weight in this population. METHODS: Ninety adolescent girls, aged 12-19 years, provided a self-assessment of weight status. Participants also completed questionnaires to assess attitudes/behaviours toward food and eating, appetitive responsiveness to the food environment, disinhibition in eating and weight history. RESULTS: Forty-three per cent of participants reported a history of overweight. Compared with participants who reported never being overweight, those who reported ever being overweight were significantly older, scored significantly higher on all measures of disordered eating attitudes/behaviours (P < or = 0.009) and were 4.8 times more likely to be currently overweight or obese (P < 0.001). Glycated haemoglobin (HbA(1c)) was similar between those who did and did not report ever being overweight. CONCLUSIONS: Because of the ill-health effects of disordered eating and the higher rate of overweight in adolescent girls with T1D, effective screening tools are warranted. The single question 'Have you ever been overweight?' may be sufficient as a first question to screen for those at high risk for disordered eating attitudes/behaviours and to provide early intervention and prevention.

Evaluating the Power of Food Scale in obese subjects and a general sample of individuals: development and measurement properties.

BACKGROUND: The Power of Food Scale (PFS) was developed to assess the psychological impact of today's food-abundant environments. OBJECTIVE: To evaluate the structure of the PFS in diverse populations of obese and nonobese individuals. DESIGN: Data were obtained from obese adults in a clinical trial for a weight management drug (n=1741), and overweight, obese and normal weight adults in a Web-based survey (n=1275). Exploratory and confirmatory factor analyses were used to investigate the PFS structure using the clinical data. The model developed was then tested using the Web-based data. Relationships between PFS domains and body mass index (BMI) were examined. Logistic regression was used in the Web-based survey to evaluate the association between obesity status and PFS scores. RESULTS: Clinical data indicated that the scale was best represented by a 15-item version with three subscale domains and an aggregate domain (average of three domains); this was confirmed with data from the Web-based survey (Comparative Fit Index: 0.95 and 0.94 for the clinical and Web-based studies, respectively). Cronbach's alpha for both data sets was high, ranging from 0.81 to 0.91. The relationships between BMI and each domain were weak (and approximately linear). A full category increase in PFS domain score (range 1-5) increased the odds of being obese 1.6-2.3 times. CONCLUSIONS: The 15-item PFS is best represented by three domains and an aggregate domain. The PFS may provide a useful tool to evaluate the effects of obesity treatments on feelings of being controlled by food in an obesogenic food environment.

Psychometric analysis of the Three-Factor Eating Questionnaire-R21: results from a large diverse sample of obese and non-obese participants.

BACKGROUND: The 21-item Three-Factor Eating Questionnaire (TFEQ-R21) is a scale that measures three domains of eating behavior: cognitive restraint (CR), uncontrolled eating (UE) and emotional eating (EE). OBJECTIVES: To assess the factor structure and reliability of TFEQ-R21 (and if necessary, refine the structure) in diverse populations of obese and non-obese individuals. DESIGN: Data were obtained from obese adults in a United States/Canadian clinical trial (n=1741), and overweight, obese and normal weight adults in a US web-based survey (n=1275). Confirmatory factor analyses were employed to investigate the structure of TFEQ-R21 using baseline data from the clinical trial. The model was refined to obtain adequate fit and internal consistency. The refined model was then tested using the web-based data. Relationships between TFEQ domains and body mass index (BMI) were examined in both populations. RESULTS: Clinical data indicated that TFEQ-R21 needed refinement. Three items were removed from the CR domain, producing the revised version TFEQ-R18V2 (Comparative Fit Index (CFI)=0.91). Testing TFEQ-R18V2 in the web-based sample supported the revised structure (CFI=0.96; Cronbach's coefficient alpha of 0.78-0.94). Associations with BMI were small. In the clinical study, the CR domain showed a significant and negative association with BMI. On the basis of the web-based survey, it was shown that the relationship between BMI and CR is population-dependent (obese versus non-obese, healthy versus diabetics). CONCLUSIONS: In two independent datasets, the TFEQ-R18V2 showed robust factor structure and good reliability. It may provide a useful tool for characterizing UE, CR and EE.

Perturbation of the activity of a single identified neuron affects long-term memory formation in a molluscan semi-intact preparation.

The aim of this study was to investigate the neural basis of operant conditioning in a semi-intact preparation of the pond snail, Lymnaea stagnalis. Lymnaea learns, via operant conditioning, to reduce its aerial respiratory behaviour in response to an aversive tactile stimulus to its open pneumostome. Here we report the successful conditioning of naïve semi-intact preparations to show ;learning in the dish' and long-term memory that persists for at least 18 h. The neurons that generate this behaviour are readily identifiable and, for the first time, we have recorded from a neuron during a training paradigm that leads to long-term memory formation in the same preparation. Specifically, we recorded from the respiratory neuron Right Pedal Dorsal 1 (RPeD1), which is part of the respiratory central pattern generator and initiates the aerial respiratory behaviour. Previous studies have shown that long-term memory of this behaviour results in reduced RPeD1 activity. In the present study, we demonstrate that preventing RPeD1 impulse activity between training sessions reduces the number of sessions needed to produce long-term memory in our semi-intact preparation.

Quantum turbulence in superfluid 3He illuminated by a beam of quasiparticle excitations.

We have measured directly the Andreev scattering of a controllable beam of quasiparticle excitations by a localized tangle of quantum vortices in superfluid 3He-B at low temperatures. We present a microscopic description of the Andreev scattering from a vortex line allowing us to estimate the vortex separation scale in a dilute tangle of vortices, providing a better comparison of the observed decay time of the turbulence with recent numerical simulations. The experiments also suggest that below 200 microK we reach the low temperature limit for turbulent dynamics.

Restrictive dieting vs. "undieting" effects on eating regulation in obese clinic attenders.

This study tested predictions from restraint theory [Herman & Polivy (1984). A boundary model for the regulation of eating. In: A. J. Stunkard, & E. Stellar (Eds.), Eating and its disorders (pp. 141-156) New York: Raven Press.] and the three-factor model of dieting [Psychol. Bull. 114 (1993) 100.] using an eating regulation paradigm. Participants were 42 obese, nonbinge eaters assigned to either a weight loss group (restrictive dieters or RDs) or a group designed to eliminate dieting ("undieters" or UDs). Participants took part in an ostensible ice cream taste test with or without a preload, both before and after the weight control intervention. At pretest, restraint theory's prediction that participants would engage in counter-regulatory eating was not supported. At posttest, after 8 weeks of the dieting interventions, RDs increased and UDs decreased their intake following a preload, a pattern most consistent with the predictions of restraint theory. This counter-regulatory trend was observed in spite of a significant decrease in RDs' Disinhibition scale scores following treatment. Implications of these findings for restraint theory, the three-factor model of dieting, and relapse in obesity treatment were discussed.

Weight-loss maintenance in overweight individuals one to five years following successful completion of a commercial weight loss program.

OBJECTIVE: To determine weight loss maintenance among participants in a commercial weight loss program (Weight Watchers) who had reached their goal weights 1-5 y previously. DESIGN: A national sample (n=1002) was surveyed by phone to obtain demographic and weight-related information. An oversample (n=258) was recruited and weighed in person to develop a correction factor for self-reported weights in the national sample. RESULTS: Based on corrected weights, weight regain from 1 to 5 y following weight loss ranged between 31.5 and 76.5%. At 5 y, 19.4% were within 5 lb of goal weight, 42.6% maintained a loss of 5% or more, 18.8% maintained a loss of 10% or more, and 70.3% were below initial weight. CONCLUSIONS: These results are not directly comparable to those obtained in clinical settings because of differences in the populations studied. Nonetheless, they suggest that the long-term prognosis for weight maintenance among individuals who reach goal weight in at least one commercial program is better than that suggested by existing research.

Seizures, lateral decubitus, aspiration, and shoulder dislocation: Time to change the guidelines?

The recommendation to position a patient having a seizure on a lateral decubitus is aimed at minimizing the risk of aspiration. The authors reviewed the database of the Epilepsy Foundation Clinic of South Florida for patients with epilepsy treated for pneumonia between May 1999 and May 2000 and patients admitted to two university telemetry units who had dislocation of the shoulder during an epileptic seizure. Over 2 months, 2 of 733 adults with intractable seizures had aspiration pneumonia after a generalized tonic clonic seizure (GTCS). Although no study has specifically addressed the problem of aspiration pneumonia in adults with GTCS, our findings suggest this problem is not common. From the two epilepsy centers, 5 of 806 patients dislocated a shoulder during a seizure. Video recordings showed that these patients were positioned in a lateral decubitus by staff while still having the convulsion. The dislocated shoulder in all cases was on the lower side. The risk of shoulder dislocation in a convulsing patient positioned in a lateral decubitus is less than 1%. Nevertheless, dislocations can result in disabling recurrences and are easily preventable. Because aspiration is more likely in the postictal rather than ictal phase of a GTCS, when oral secretions are not usually increased and there is cessation of respiratory movements, lateral decubitus should only be implemented after cessation of the convulsion, In inpatients (such as those on telemetry), secretions may be better managed by bedside aspiration of the oral cavity.

Increased seizures after discontinuing carbamazepine: results from the gabapentin monotherapy trial.

Studies in patients with epilepsy undergoing telemetry evaluation for surgery have suggested that discontinuation of carbamazepine (CBZ) is associated with increased seizures. The period of observation in that setting, however, was limited to a few days. The authors reviewed the occurrence of seizures in patients with epilepsy who had all their antiepileptic medications discontinued during an 8-week period, converted to gabapentin monotherapy, and observed for 26 weeks as part of the gabapentin trial #945-082. Two hundred and seventy-five patients were enrolled. Kaplan-Meier estimates of time to exit for all patients showed that 18% of patients previously treated with CBZ completed the study as compared with 30% of the patients receiving other antiepileptic medications. Increase in the frequency of seizures was maximal in the 2 weeks following CBZ discontinuation. Seizures increased both in frequency and severity but no new seizure types were observed. The findings in this study show that removal of CBZ is associated with increased frequency of seizures in patients with a previous history of epilepsy with incompletely controlled seizures. The period of maximal increase was the first 2 weeks after CBZ discontinuation.

Persisting aphasia as the sole manifestation of partial status epilepticus.

OBJECTIVES: Persisting aphasia presenting as an isolated inability to vocalize is an uncommon presentation of simple partial status epilepticus and only eight such cases have been reported over the past 40 years. METHODS: We studied a patient with a 5-year history of recurrent episodes of inability to talk, without any other motor or cognitive impairments. Episodes lasted as long as 24 h, interictal EEGs were normal and she was diagnosed as a conversion disorder. RESULTS: EEG recordings during one of the episodes showed continuous discharges in the right frontal and parasagital areas demonstrating the ictal nature of the deficits. During the episode the patient had no deficits of strength, or in her ability to perform skilled movements to command, imitation or manipulation of objects. Comprehension of complex verbal commands was preserved and she would make attempts to articulate words and correctly answered questions with head nodding or monosyllables, yes or no. She could hum but had no other vocalizations. CONCLUSIONS: This is the first case of aphasic status epilepticus secondary to epileptogenic discharges of the right hemisphere. The case is also unique for the isolated involvement of production of language during the seizure.

Nonepileptic seizures in pregnancy.

The authors report five patients with recurrent psychogenic seizures (PS) during pregnancy, with multiple emergency room visits and continued intake of antiepileptic drugs obtained from various sources, despite awareness of the psychogenic nature of their attacks and the risks of antiepileptic drug use in pregnancy. These patients demonstrate that preexisting PS may persist during pregnancy, and there will be patients who continue to take antiepileptic drugs despite awareness of the risks inherent to these treatments. New-onset or persisting PS with pregnancy can be indicative of serious emotional conflicts, and the child should be considered at risk.