Hedonic Deficits Research Articles

Pain, hedonic regulation, and opioid misuse: Modulation of momentary experience by Mindfulness-Oriented Recovery Enhancement in opioid-treated chronic pain patients

BackgroundGiven the risk of opioid misuse among chronic pain patients being treated with long-term opioid pharmacotherapy, non-pharmacological treatments are needed. Further, in light of hedonic deficits in this population, therapies that enhance positive affect may be useful. The purpose of this study was to examine effects of a Mindfulness-Oriented Recovery Enhancement (MORE) intervention on ecological momentary assessments (EMA) of pain and positive affective experience, and to determine if changes in pain, affect, and their interaction were associated with opioid misuse at post-treatment. MethodsThis study examined unpublished EMA data from a subset of participants (N=55) in a previously published RCT (NCT01505101) of MORE versus a support group (SG) control. Across 8 weeks of treatment, patients completed up to 224 EMA measures of pain and affect. Multilevel models and generalized estimating equations examined effects of treatment on momentary pain and positive affect, and generalized linear models examined associations between pain and affect and changes in opioid misuse by post-treatment. ResultsPatients in MORE reported significantly greater improvements in momentary pain (p=0.01) and positive affect (p=0.004) than patients in the SG. Further, over the entire course of treatment, patients in MORE were significantly more likely to exhibit positive affect regulation (OR=2.75) than patients in the SG. Finally, improvements in positive affect (but not pain) over the course of intervention were associated with reduced risk of misusing opioids by post-treatment (p=0.02). ConclusionMORE may be a useful non-pharmacological treatment for pain and hedonic deficits among chronic pain patients at risk for opioid misuse.

Methamphetamine Induces Anhedonic-Like Behavior and Impairs Frontal Cortical Energetics in Mice.

We recently showed that a single high dose of methamphetamine (METH) induces a persistent frontal cortical monoamine depletion that is accompanied by helpless-like behavior in mice. However, brain metabolic alterations underlying both neurochemical and mood alterations remain unknown. Herein, we aimed at characterizing frontal cortical metabolic alterations associated with early negative mood behavior triggered by METH. Adult C57BL/6 mice were injected with METH (30 mg/kg, i.p.), and their frontal cortical metabolic status was characterized after probing their mood and anxiety-related phenotypes 3 days postinjection. Methamphetamine induced depressive-like behavior, as indicated by the decreased grooming time in the splash test and by a transient decrease in sucrose preference. At this time, METH did not alter anxiety-like behavior or motor functions. Depolarization-induced glucose uptake was reduced in frontocortical slices from METH-treated mice compared to controls. Consistently, astrocytic glucose transporter (GluT1) density was lower in the METH group. A proton high rotation magic angle spinning (HRMAS) spectroscopic approach revealed that METH induced a significant decrease in N-acetyl aspartate (NAA) and glutamate levels, suggesting that METH decreased neuronal glutamatergic function in frontal cortex. We report, for the first time, that a single METH injection triggers early self-care and hedonic deficits and impairs frontal cortical energetics in mice.

The neural transfer effect of working memory training to enhance hedonic processing in individuals with social anhedonia.

Anhedonia, the diminished ability to experience pleasure, is a challenging negative symptom in patients with schizophrenia and can be observed in at-risk individuals with schizotypy. Deficits in hedonic processing have been postulated to be related to decreased motivation to engage in potentially rewarding events. It remains unclear whether non-pharmacological interventions, such as cognitive training, could improve anhedonia. The present study aimed to examine the neural mechanism for alleviating hedonic deficits with working memory (WM) training in individuals with social anhedonia. Fifteen individuals with social anhedonia were recruited and received 20 sessions of training on a dual n-back task, five sessions a week. Functional imaging paradigms of the Monetary Incentive Delay (MID) and the Affective Incentive Delay (AID) tasks were administered both before and after the training to evaluate the neural transfer effects on hedonic processing ability. Enhanced brain activations related to anticipation were observed at the anterior cingulate cortex, the left dorsal striatum and the left precuneus with the AID task, and at the dorsolateral prefrontal cortex and the supramarginal gyrus with the MID task. The present findings support that WM training may improve monetary-based and affective-based hedonic processing in individuals with social anhedonia.

The effects of working memory training on enhancing hedonic processing to affective rewards in individuals with high social anhedonia.

Anhedonia is a core feature of the negative symptoms of schizophrenia and is less responsive to antipsychotic medication. Little is known whether anhedonia could be alleviated by cognitive training. The present study aimed to examine whether hedonic deficits observed in individuals with high social anhedonia could be reduced by working memory (WM) training. Thirty-four individuals with high social anhedonia were randomly assigned to either a WM training group or a control group. The WM training group received 20 sessions of dual n-back task training for four weeks. The affective incentive delay task was administered in all participants before the training and one month later. The results showed that individuals who received the WM training showed significant improvement in WM performance (F(19, 304)=55.80, p<0.001) and they also showed significant improvement in approach sensitivity to rewards (p=0.004). These preliminary findings suggest that hedonic processing could be improved through WM training in individuals with high social anhedonia. These results may have important implications for the development of non-pharmacological interventions to alleviate anhedonia in patients with schizophrenia.

Everybody's working for the weekend: changes in enjoyment of everyday activities across the retirement threshold.

the aim of this study was to explore the associations between use of time and momentary hedonic affect ('enjoyment') in adults in the peri-retirement period. a total of 124 adults [61 males, 63 females; age 62 (4) years] completed a computerised use-of-time recall on 4 days at each of four time points (3-6 months pre-, 3, 6 and 12 months post-retirement), as well as surveys regarding self-reported health, well-being, sleep quality and loneliness. They reported how much they enjoyed each activity on a 0-10 scale. An individual Enjoyment Index was calculated as the time-weighted average of each participant's enjoyment ratings. Time-weighted enjoyment ratings were also calculated for nine mutually exclusive and exhaustive activity domains (Sleep, Chores, Work, Social, Screen Time, Self-care, Quiet Time, Transport, Physical Activity) and sub-domains. the mean (±SD) Enjoyment Index was 7.43 ± 0.61, and was significantly and positively associated with well-being (P = 0.003 to P < 0.0001) and sleep quality (P = 0.03 to P < 0.0001), and negatively associated with loneliness (P = 0.003 to P < 0.0001). Mean Enjoyment Index values increased significantly (P < 0.0001) from pre-retirement (7.19 ± 0.82) to post-retirement (7.46 ± 0.89, 7.42 ± 0.91 and 7.49 ± 0.89 at 3, 6 and 12 months post-retirement). There were significant differences in enjoyment across domains, with Physical Activity (7.86 ± 1.11) and Social (7.66 ± 0.85) being the most enjoyable, and Work (7.10 ± 0.89) and Chores (7.09 ± 0.85) the least enjoyable. enjoyment of everyday activities increased after retirement and remained elevated for at least 12 months. Work appears to constitute a relative hedonic deficit.

Hedonic Capacity in the Broader Autism Phenotype: Should Social Anhedonia Be Considered a Characteristic Feature?

Impairments in social motivational processes may partially explain the differences in social interaction seen among individuals with autism spectrum disorder (ASD). The social motivation hypothesis would predict an association between reduced hedonic capacity and ASD. However, to date, findings have been mixed regarding hedonic deficits among individuals with ASD; adults report lower levels of both social and physical pleasure whereas adolescents only report experiencing lower social pleasure. Moreover, very few studies examining the association between anhedonia and autistic traits have used measures of hedonic response or taken temporal aspects of pleasure into account. The present study examined associations between autistic traits and the experience of pleasure using a non-clinical sample of young adults to further clarify the nature of hedonic deficits in the broader autism phenotype (BAP). Results revealed that autistic traits were negatively associated with both the experience of social pleasure as well as general pleasure, although the association was stronger for social pleasure. Regression analyses revealed that reduced social pleasure was a better predictor of autistic traits than general pleasure. Together these findings suggest that reduced social hedonic capacity is associated with autistic traits in the general population and should be included in conceptualizations of the BAP.

Experiential pleasure deficits in the prodrome: A study of emotional experiences in individuals at ultra-high risk for psychosis and recent-onset schizophrenia

BackgroundPrevious studies report deficits in noncurrent but not current pleasure experience in schizophrenia, but little is known about pleasure experiences of the prodrome. This study investigated noncurrent and current pleasure experiences and its relationship with neurocognitive function and self-esteem in ultra-high risk (UHR) for psychosis and recent-onset schizophrenia (ROSPR). MethodsTwenty-four UHR, 25 ROSPR and 42 normal controls completed the physical and social anhedonia scales for noncurrent emotional experience and the laboratory-based assessment of valence and arousal evoked by positive, neutral and negative emotional stimuli for current emotional experience. Relationships of current and noncurrent emotional experience, episodic memory and self-esteem were investigated. ResultsFor ROSPR, noncurrent pleasure, but not current pleasure evoked by positive stimuli, was diminished. Noncurrent anhedonia in ROSPR was related to episodic memory deficits and low self-esteem. In UHR subjects, both noncurrent pleasure and current pleasure to positive and neutral stimuli were diminished. Noncurrent anhedonia in UHR was not associated with episodic memory nor self-esteem. For arousal, ROSPR patients showed higher arousal than UHR subjects to positive stimuli. ConclusionsFindings indicate the presence of experiential hedonic deficits during the prodrome phase. Diminished noncurrent pleasure reports exist in ROSPR, which seems to be associated with cognitive deficits and low self-concept. Future research is needed to probe into further underlying mechanisms.

Long-lasting deficits in hedonic and nucleus accumbens reactivity to sweet rewards by sugar overconsumption during adolescence.

Adolescence is a critical period characterized by major neurobiological changes. Chronic stimulation of the reward system might constitute an important factor in vulnerability to pathological development. In spite of the dramatic increase in the consumption of sweet palatable foods during adolescence in our modern societies, the long-term consequences of such exposure on brain reward processing remain poorly understood. Here, we investigated in rats the long-lasting effects of sugar overconsumption during their adolescence on their adult reactivity to the hedonic properties of sweet rewards. Adolescent rats with continuous access to 5% sucrose solution (from postnatal day 30-46) showed escalating intake. At adulthood (post-natal day 70), using two-bottle free choice tests, sucrose-exposed rats showed lower intake than non-exposed rats suggesting decreased sensitivity to the rewarding properties of sucrose. In Experiment 1, we tested their hedonic-related orofacial reactions to intraoral infusion of tasty solutions. We showed that sucrose-exposed rats presented less hedonic reactions in response to sweet tastes leaving the reactivity to water or quinine unaltered. Hence, in Experiment 2, we observed that this hedonic deficit is associated with lower c-Fos expression levels in the nucleus accumbens, a brain region known to play a central role in hedonic processing. These findings demonstrate that a history of high sucrose intake during the critical period of adolescence induces long-lasting deficits in hedonic treatment that may contribute to reward-related disorders.

Chronic mild stress in submissive mice: Marked polydipsia and social avoidance without hedonic deficit in the sucrose preference test

In the Chronic Mild Stress (CMS) protocol, rodents are exposed to unpredictable stressors to induce anxiety-like behavior and hedonic deficit in the Sucrose Preference test (SPT). Since CMS-induced anxiety- and anhedonic-like behavior may depend upon individual vulnerability to stress, we hypothesized that selectively bred Submissive (Sub) mice would exhibit heightened anxiety- and anhedonic-like behavior, in response to CMS exposure. We anticipated that the testing of Sub mice alongside their Wt counterparts in a battery of behavioral assays would identify parameters most sensitive to CMS effects. To test these assumptions, Sub mice and their outbred Sabra (Wt) counterparts underwent a five-week CMS-SPT regimen.CMS exposure led to reduced preference for sucrose (sucrose-sweetened water as percent of total intake) among both mouse strains (p<0.01 Wt; p<0.05 Sub). However, this effect was attributed to CMS-induced polydipsia, indicated by mice’s increased water consumption, (p<0.01 Wt and Sub), without changes in sucrose intake. Furthermore, CMS-exposed Sub mice, but not Wt, demonstrated impaired social exploration in the Three Chamber test (p<0.05) and anxiety-like effects in the Elevated Plus Maze (p<0.05). Moreover, in a separate experiment, social isolation alone was sufficient to induce polydipsia in Sub mice, without affecting Wt mice’s drinking behavior. The present findings suggest that the EPM and Three Chamber tests may be valuable complementary measures of CMS effects, alongside the Sucrose Preference test, and introduce the Sub mouse strain for use in study of susceptibility to stress.

Mechanisms Underlying Motivational Deficits in Psychopathology: Similarities and Differences in Depression and Schizophrenia.

Motivational and hedonic impairments are core aspects of a variety of types of psychopathology. These impairments cut across diagnostic categories and may be critical to understanding major aspects of the functional impairments accompanying psychopathology. Given the centrality of motivational and hedonic systems to psychopathology, the Research Domain Criteria (RDoC) initiative includes a "positive valence" systems domain that outlines a number of constructs that may be key to understanding the nature and mechanisms of motivational and hedonic impairments in psychopathology. These component constructs include initial responsiveness to reward, reward anticipation or expectancy, incentive or reinforcement learning, effort valuation, and action selection. Here, we review behavioral and neuroimaging studies providing evidence for impairments in these constructs in individuals with psychosis versus in individuals with depressive pathology. There are important differences in the nature of reward-related and hedonic deficits associated with psychosis versus depression that have major implications for our understanding of etiology and treatment development. In particular, the literature strongly suggests the presence of impairments in in-the-moment hedonics or "liking" in individuals with depressive pathology, particularly among those who experience anhedonia. Such deficits may propagate forward and contribute to impairments in other constructs that are dependent on hedonic responses, such as anticipation, learning, effort, and action selection. Such hedonic impairments could reflect alterations in dopamine and/or opioid signaling in the striatum related to depression or specifically to anhedonia in depressed populations. In contrast, the literature points to relatively intact in-the-moment hedonic processing in psychosis, but provides much evidence for impairments in other components involved in translating reward to action selection. Particularly, individuals with schizophrenia exhibit altered reward prediction and associated striatal and prefrontal activation, impaired reward learning, and impaired reward-modulated action selection.

Hedonic Deficits in Parkinson’s Disease: Is Consummatory Anhedonia Specific?

Background: Anhedonia, the lowered ability to experience pleasure, is one of the non-motor symptoms of Parkinson’s disease (PD) that is underdiagnosed and consequently undertreated. Few studies have investigated anhedonia in PD by taking into account the influence of socio-demographic variables and versus a control group composed of patients with a pure motor neurologic disease other than PD. The aim of this study was to investigate hedonic deficits in patients with PD compared to a control group of patients with non-Parkinson motor neurologic disease (OND), matched for age, gender, level of education, and inpatient/outpatient status. Distinctions between anticipatory and consummatory anhedonia and between endogenomorphic and non-endogenomorphic depression were taken into account.Methods: The study population comprised 49 PD patients and 40 subjects with OND. Anhedonia was rated by using the anticipatory [Temporal Experience Pleasure Scale (TEPS)-ANT] and consummatory (TEPS-CONS) subscales of the TEPS and two subscales extracted from the revised Physical Anhedonia Scale (PAS), measuring physical anticipatory (PAS-ANT) and physical consummatory (PAS-CONS) anhedonias. The Snaith–Hamilton Pleasure Scale (SHAPS) and the Beck Depression Inventory-II (BDI-II) were also used together with a subscale extracted from the BDI-II (ENDO-BDI-II) for the diagnosis of endogenomorphic depression. Statistical analyses were performed on the whole group and on the PD group.Results: As hypothesized, several anhedonia scores varied with age and gender in the whole population or in the PD group. On univariate or multivariate analyses, only PAS-CONS was specific for PD and only SHAPS scores differed between depression subtypes in the whole population or the PD group.Conclusion: This study suggests that physical consummatory anhedonia could be specific to PD subjects.

Domain-specific hedonic deficits towards social affective but not monetary incentives in social anhedonia

Anticipatory and consummatory dissociation of hedonic experience may manifest as anhedonia in schizophrenia. However, it is unclear if this temporal dissociation of pleasure experience is also relevant in other symptoms like social anhedonia in the schizophrenia disorder spectrum. The present study applied two incentive delay tasks involving different incentive types (money vs. social affective images) to a sample of 28 participants with elevated social anhedonia (SocAnh) and 38 healthy controls from a population of 476 college students. The results showed that the SocAnh group had comparable anticipatory sensitivity and consummatory pleasure towards monetary incentives as the controls; but they exhibited significant decrease in both anticipatory sensitivity and consummatory experience to positive social affective images. These findings demonstrate the presence of a domain-specific deficit in people with social anhedonia towards social affective information, and suggest that incentive types could confound the findings on the dissociation of anticipatory vs. consummatory hedonic capacities.

Negative symptoms of schizophrenia: Clinical features, relevance to real world functioning and specificity versus other CNS disorders

Negative symptoms have long been recognized as a central feature of the phenomenology of schizophrenia, dating back to the early descriptions by Kraepelin and Bleuler. Over the ensuing century, there have been important clarifications and reconceptualizations regarding the phenomenology of negative symptoms in schizophrenia. This review explores these developments, including the delineation of two underlying subdomains of negative symptoms – amotivation (i.e., avolition/apathy and asociality) and diminished expression (i.e., poverty of speech and affective flattening). Further, advances in our understanding of specific motivational and hedonic deficits seen in schizophrenia are explored. The findings that negative symptoms stand apart from depressive and cognitive symptoms in schizophrenia are also discussed. In terms of the predictors of functional outcomes in schizophrenia, we explore both the direct role of negative symptoms in this regard, as well as their indirect role through cognition. We then broaden our examination of negative symptoms to related disorders across the schizophrenia spectrum, as well as to other neuropsychiatric illnesses, where negative symptoms have been increasingly recognized. We explore the differential characteristics of negative symptoms across these illnesses, and their relevance to functional outcomes. This transdiagnostic presence and relevance of negative symptoms highlights the need for continued exploration of their phenomenology and neurobiology as we move to develop effective interventions to address these debilitating symptoms and improve functional outcomes.

Melatonin ameliorates chronic mild stress induced behavioral dysfunctions in mice

Melatonin, a neurohormone, is known to regulate several physiological functions, especially the circadian homeostasis, mood and behavior. Chronic exposure to stress is involved in the etiology of human affective disorders, and depressed patients have been reported to show changes in the circadian rhythms and nocturnal melatonin concentration. The present study was conducted to evaluate a possible beneficial action of chronic night-time melatonin treatment against chronic mild stress (CMS) induced behavioral impairments. As expected in the present study, the stress exposed mice showed reduced weight gain, hedonic deficit, cognitive deficits and decreased mobility in behavioral despair test. Interestingly, CMS exposed mice showed less anxiety. Chronic night-time melatonin administration significantly ameliorated the stress-induced behavioral disturbances, especially the cognitive dysfunction and depressive phenotypes. In conclusion, the present findings suggest the mitigating role of melatonin against CMS-induced behavioral changes, including the cognitive dysfunctions and reaffirm its potential role as an antidepressant.

Anhedonic-like traits and lack of affective deficits in 18-month-old C57BL/6 mice: Implications for modeling elderly depression

The prevalence of depression increases with aging. We hypothesized that like humans, old animals exhibit anhedonic-like behavior, along with signs of behavioral despair. In rodents, anhedonia, a reduced sensitivity to reward, which is listed as a core feature of major depression in the DSM-IVR, can be measured by a decrease in intake of and preference for sweet solutions. Here, sucrose intake, forced swimming, immobility in the modified tail suspension test, novelty exploration, grooming, anxiety and locomotor activity were compared in naïve 3- and 18-month-old male C57BL/6 mice. The absolute amounts and the ratio of consumed 1% sucrose solution to water intake was significantly smaller in 18-month-old mice than in 3-month-old mice. The consumption of 5%-sucrose solution requiring high levels of drinking effort, novelty exploration in two setups and grooming behavior in the splash test were reduced in older animals. Analysis of other behaviors suggested that the above-mentioned signs of anhedonic-like traits were unlikely to be attributable to the potential effect of aging on metabolic needs for water, taste perception, motor capabilities or the induction of essential anxiety and neophobia. A 4-week treatment with the antidepressant imipramine (7mg/kg/day) or dimebon, a compound with suggested neuroprotective proneurogenic properties (1mg/kg/day) restored sucrose intake and preference in 18-month-old mice. Meanwhile, young and old mice showed no differences in the parameters of behavioral despair evaluated in the forced swim and modified tail suspension tests. Thus, the behavioral profile of aged mice parallels that of humans with elderly depression, in whom the symptoms of hedonic deficits typically outweigh affective disturbances. The assessment of anhedonic-like traits with the sucrose preference test in 18-month-old mice will be useful in preclinical studies of elderly depression.

Assessment of anhedonia in psychological trauma: development of the Hedonic Deficit and Interference Scale

Symptoms of anhedonia, or deficits in the ability to experience positive affect, are increasingly recognized as an outcome of traumatic stress. Herein we demonstrate a phenomenon of “negative affective interference”, specifically, negative affective responses to positive events, in association with childhood trauma history. Young adults (n=99) completed a Hedonic Deficit & Interference Scale (HDIS), a self-report measure developed for this study, as well as a modified version of the Fawcette-Clarke Pleasure Capacity Scale that assessed not only positive but also negative affective responses to positive events. The two assessment approaches demonstrated convergent validity and predicted concurrent individual differences in trait positive and negative affect, and extraversion and neuroticism. Histories of childhood emotional and sexual abuse were differentially associated with negative affective responses to positive events. Future research and clinical directions are discussed.For the abstract or full text in other languages, please see Supplementary files under Reading Tools online.

Assessment of anhedonia in psychological trauma: psychometric and neuroimaging perspectives

Symptoms of anhedonia, or deficits in the ability to experience positive affect, are increasingly recognized as an outcome of traumatic stress including in individuals with PTSD. However, little research has investigated negative affective responses to what would normally be considered pleasant events (e.g., receiving a compliment or gift, physical affection) in traumatized persons. We demonstrate not only self-reported decreased positive affect but also increased negative affect in response to positive events in 55 women with PTSD, in comparison with 35 women without PTSD, via their response to a Hedonic Deficit & Interference Scale (HDIS). The HDIS demonstrated strong internal validity, convergent and incremental validity relative to other measures of anhedonia, and discriminant validity in relation to depression versus anxiety symptoms in this sample. In addition, in response to imagery of social versus non-social positive events, HDIS scores predicted self-report positive and negative affective responses. In a sub-sample of participants completing the imagery task while undergoing fMRI (n=12), HDIS scores also predicted BOLD response within the left orbitofrontal cortex, ventromedial prefrontal cortex, amygdala, and cerebellum. Future research and clinical directions are discussed.For the abstract or full text in other languages, please see Supplementary files under Reading Tools online.

Anhedonia Is an Important Factor of Health-Related Quality-of-Life Deficit in Schizophrenia and Schizoaffective Disorder

The aim of the current study was to investigate an association of physical and social hedonic deficits with health-related quality of life (HRQL), controlling for related distressing and protective factors. Eighty-seven stable patients with schizophrenia (SZ) and schizoaffective disorder (SA) were assessed using the revised Physical Anhedonia Scale (PAS) and the Social Anhedonia Scale (SAS), the Quality of Life Enjoyment and Life Satisfaction Questionnaire (Q-LES-Q), and related factors. Hedonic and HRQL deficit scores did not reach significant differences between SZ and SA patients. General and domain-specific Q-LES-Q scores were significantly correlated with PAS and SAS scores independent of the adverse effects and psychopathological symptoms. Dissatisfaction with HRQL increased from "normal hedonics" (4.8%) to "hypohedonics" (28.6%) and "double anhedonics" (66.7%). Permanently dissatisfied patients who revealed deterioration in general quality of life across 10 years had significantly higher PAS and SAS scores than did patients who were permanently satisfied and improved. An exploratory factor analysis yielded a three-factor solution; PAS and SAS scores were joined to the second factor together with Q-LES-Q, self-efficacy, coping styles, and social support scores. PAS scores accounted for 7% to 13% of the total variance in three domains and in the general quality-of-life alterations. SAS scores did not predict variability in the Q-LES-Q domains. Therefore, physical and social hedonic deficits significantly associated with poor HRQL independent of the adverse effects and psychopathological symptoms of SZ/SA. Physical anhedonia may be a predictor for quality-of-life deficit.

Emotional Experience in Negative Symptoms of Schizophrenia—No Evidence for a Generalized Hedonic Deficit

Deficits in emotion processing are thought to underlie the key negative symptoms flat affect and anhedonia observed in psychotic disorders. This study investigated emotional experience and social behavior in the realm of daily life in a sample of patients with schizophrenia and schizoaffective disorder, stratified by level of negative symptoms. Emotional experience and behavior of 149 patients with schizophrenia and schizoaffective disorder and 143 controls were explored using the Experience Sampling Method. Patients reported lower levels of positive and higher levels of negative affect compared with controls. High negative symptom patients reported similar emotional stability and capacity to generate positive affect as controls, whereas low negative symptom patients reported increased instability. All participants displayed roughly comparable emotional responses to the company of other people. However, in comparison with controls, patients showed more social withdrawal and preference to be alone while in company, particularly the high negative symptom group. This study revealed no evidence for a generalized hedonic deficit in patients with psychotic spectrum disorders. Lower rather than higher levels of negative symptoms were associated with a pattern of emotional processing which was different from healthy controls.

Anticipatory vs. consummatory pleasure: What is the nature of hedonic deficits in schizophrenia?

Recent research has distinguished between anticipatory and consummatory pleasure. In the current study, we examined the psychometric properties of the Temporal Experience of Pleasure Scale (TEPS) to determine whether reliability and validity findings reported in previous research replicate in an additional sample of schizophrenia patients. Participants included 86 individuals with schizophrenia and 59 demographically matched healthy controls. Inconsistent with previous research, patients differed from controls in their reports of consummatory (TEPS-CON), but not anticipatory (TEPS-ANT) pleasure. We also failed to replicate some important correlational findings reported in previous research indicating relationships between the TEPS-ANT subscale and external validators. Analyses of the stability of the TEPS subscales were conducted in a sub-group of patients ( n = 19), and indicated excellent stability for the TEPS-CON (ICC (intraclass correlation coefficient) = 0.93), but somewhat lower stability for the TEPS-ANT subscale (ICC = 0.74). These findings suggest that additional studies are needed using the TEPS, as well as other measures, to determine the nature of anhedonia in individuals with schizophrenia.