Categorization in compulsive hoarding

Based on hypothesizing about the role of information processing, and in particular, underinclusive categorization in compulsive hoarding, this study examined categorization processes in people with clinically significant compulsive hoarding problems. Twenty-one participants with primary compulsive hoarding, 21 with OCD without hoarding, and 21 non-psychiatric controls completed three categorization tasks. Hoarding and OCD participants reported significantly more distress prior to each of the three tasks than did controls. On tasks sorting common household items, the groups did not differ on the number of piles created nor on the amount of time taken to sort. However, on a task sorting personally relevant items, hoarding participants took more time, created more piles, and reported more anxiety than non-psychiatric controls. Hoarders also took more time than the OCD group, and tended to create more piles. Hoarding severity was correlated with the number of piles created, but only when the objects were personally relevant. Results support under-inclusive categorizing for people with compulsive hoarding, but the effect was largely confined to objects of personal relevance.     

Neuropsychological impairment associated with compulsive hoarding

A group of patients with compulsive hoarding (n=30) was compared to a mixed clinical group (n=30) and a nonclinical community group (n=30) on laboratory tests of information-processing features hypothesized to be central to hoarding (memory, attention, and decision-making). Hoarding patients demonstrated slower and more variable reaction time, increased impulsivity, greater difficulty distinguishing targets and nontargets, and worse spatial attention relative to comparison groups. Multiple regression analyses demonstrated that slower reaction time and increased impulsivity were significantly related to hoarding symptoms over and above the effect of depression, schizotypy, and other obsessive-compulsive disorder (OCD) symptoms. There were no group differences on a test of emotion-based decision-making. Results are discussed in terms of previous findings and theoretical models of compulsive hoarding.     

The prevalence of compulsive hoarding and its association with compulsive buying in a German population-based sample

The aims of the study were to estimate the prevalence rate of compulsive hoarding, and to determine the association between compulsive hoarding and compulsive buying in a nationally representative sample of the German population (N = 2307). Compulsive hoarding was assessed with the German version of the Saving Inventory-Revised (SI-R; Frost, R.O., Steketee, G., & Grisham, J. (2004). Measurement of compulsive hoarding: saving inventory-revised. Behaviour Research and Therapy, 42, 1163-1182.). The point prevalence of compulsive hoarding was estimated to be 4.6%. Individuals with compulsive hoarding did not differ significantly from those without compulsive hoarding regarding age, gender, and other sociodemographic characteristics. Significant correlations were found between the compulsive hoarding and the compulsive buying measures. Participants with compulsive hoarding reported a higher propensity to compulsive buying than respondents without hoarding. About two thirds of participants classified as having compulsive hoarding were also defined as suffering from compulsive buying. In summary, these results suggest that compulsive hoarding may be relatively prevalent in Germany and they confirm the close association between compulsive hoarding and compulsive buying through the investigation of a large scale representative sample.     

Hoarding in a compulsive buying sample

Previous research has indicated that many compulsive buyers also suffer from compulsive hoarding. The present work specifically examined hoarding in a compulsive buying sample. Sixty-six treatment-seeking compulsive buyers were assessed prior to entering a group therapy for compulsive buying using the Compulsive Buying Scale (CBS), the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS)-Shopping Version, the Compulsive Acquisition Scale (CAS), the German-CBS, the Saving Inventory-Revised (SI-R), the Maudsley Obsessive Compulsive Inventory (MOCI), the Barratt Impulsiveness Scale (BIS-11), and the Structured Clinical Interview for DSM-IV Axis I (SCID). Inclusion criteria were current problems with compulsive buying according to the proposed diagnostic criteria for compulsive buying by McElroy, Keck, Pope, Smith, and Strakowski [(1994). Compulsive buying: A report of 20 cases. Journal of Clinical Psychiatry, 55, 242-248]. Our results support the assumption that many but not all compulsive buyers suffer from compulsive hoarding. A significant association between the SI-R and the compulsive buying measures CBS, Y-BOCS-SV, German-CBS, and the CAS-Buy subscale was found, which is mostly caused by the SI-R subscale acquisition. The SI-R subscales clutter and difficulty discarding were more closely associated with the CAS-Free subscale and with obsessive-compulsive symptoms. Hoarding compulsive buyers reported more severe buying symptoms and obsessive-compulsive symptoms and presented with a higher psychiatric co-morbidity, especially any current affective, anxiety and eating disorder. Specific therapeutic interventions for compulsive buyers who also report compulsive hoarding appear indicated.     

Family burden of compulsive hoarding: results of an internet survey

Compulsive hoarding, the acquisition of and failure to discard large numbers of possessions, is associated with substantial health risk, impairment in functioning, and economic burden. Despite clear indications that hoarding has a detrimental effect on people living with or near someone with a hoarding problem, no empirical research has examined these harmful effects. The aim of the present study was to examine the burden of hoarding on family members. Six hundred sixty-five family informants who reported having a family member or friend with hoarding behaviors completed an internet-based survey. Living with an individual who hoards during childhood was associated with elevated reports of childhood distress and family strain. Family members reported high levels of patient rejection attitudes, suggesting high levels of family frustration and hostility. Rejecting attitudes were predicted by severity of hoarding symptoms, the individual's perceived lack of insight into the behavior, and having lived in a cluttered environment during childhood. These results suggest that compulsive hoarding adversely impacts not only the hoarding individual, but also those living with them.     

When hoarding is a symptom of OCD: A case series and implications for DSM-V

Hoarding, the excessive collection and failure to discard objects of apparently little value, can represent a serious psychiatric problem and pose a threat to public health. Hoarding has traditionally been considered a symptom (or symptom dimension) of Obsessive-Compulsive Disorder (OCD), but its nosological status has recently been debated. Mounting evidence suggests that, once other primary causes are ruled out, hoarding may be a discrete diagnostic entity, recently named Hoarding Disorder. However, hoarding can sometimes be a genuine OCD symptom. This can be confusing and clinicians may sometimes struggle making the differential diagnosis. To illustrate this, we describe 10 OCD patients with severe hoarding behavior that is better conceptualized as a symptom of OCD. We focus on the motivations for hoarding and the overlapping of hoarding with other obsessive-compulsive symptom dimensions. We estimate that this clinical presentation is relatively rare and accounts for a minority of severe hoarding cases. We discuss the unique characteristics of hoarding as a symptom of OCD and the implications for DSM-V.     

Dissimilarity in Creative Categorization

Theories of categorization need to account for ways in which people use their creativity to categorize things, especially in the context of similarity. The current three‐phase study is a preliminary attempt to understand how people group concepts together as well as to explore the role of similarity between concepts in creative categorization. Participants were asked to categorize a list of 100 words and the resulting categories were rated for creativity by another set of participants. In the last phase, similarity between words from all the categories was computed using latent semantic analysis. There was a significant correlation between similarity values and creativity ratings for all the categories. In addition, a new set of participants were asked to rate the similarity among the words in the least and most creative categories and there was a significant difference between the mean ratings of the two types of categories. The results indicate that creative categorization is characterized by grouping of dissimilar words. People use creative imagination to construct novel categories by linking apparently dissimilar words.     

Comparison of treatment seeking compulsive buyers in Germany and the United States

OBJECTIVE: The aim of this pilot study was to compare a German (Bavaria) and an American (North Dakota) sample of women suffering from compulsive buying. METHOD: Thirty-eight German and 39 American female compulsive buyers were screened with the Compulsive Buying Scale (CBS), and the Yale-Brown Obsessive Compulsive Scale-Shopping Version (Y-BOCS-SV) prior to entering a group treatment study. Psychiatric co-morbidity was assessed with the Structured Clinical Interview for DSM-IV Axis I disorders (SCID). RESULTS: There were no statistically significant differences between the German sample and the American sample with regard to age (mean 43.7 and 45 years, respectively), and with regard to the scores on the CBS and the Y-BOCS-SV. A high lifetime co-morbidity rate with Axis I disorders, especially mood disorders, anxiety disorders, substance use disorders, OCD, and binge eating disorder was detected in both samples. Almost all participants met criteria for at least one lifetime Axis I disorder. However, German compulsive buyers showed significantly higher current prevalence rates of any affective disorder, and higher current and lifetime prevalence rates of any anxiety disorder and somatoform disorder. In addition, German compulsive buyers were significantly more likely to have more than one Axis I disorder. CONCLUSION: The groups did not differ with regard to age and with regard to the severity of compulsive buying and showed a high co-morbidity with Axis I disorders. However, the German compulsive buying sample presented with significantly more psychiatric co-morbidity compared to the American sample. Further research is needed to provide a better understanding of this disorder in general and cross-culturally.     

Inhibition and shifting in children with learning deficits in arithmetic and reading

The executive functions of inhibition and shifting were studied in arithmetic-disabled children, reading-disabled children, reading plus arithmetic-disabled children, and controls (N = 74). Measures involved the rapid naming of objects, digits, letters, or quantities with or without additional task requirements that reflected inhibition or shifting. Also, the Making Trails task, reflecting shifting, was administered. For tasks without executive demands, arithmetic-disabled children were slower in the naming of digits and quantities, whereas reading-disabled children were slower in the naming of digits and letters. For the executive tasks, arithmetic-disabled children as well as reading plus arithmetic-disabled children were impaired on the Making Trails task and on an object naming task that required both inhibition and shifting. Reading-disabled children exhibited no problems in executive functioning. Furthermore, it was shown that reading plus arithmetic-disabled children experienced the combination of problems that characterize children with a single learning deficit.     

COMT gene polymorphisms,cognitive performance,and physical fitness in older adults

ObjectiveIt is well known that genetic predispositions might influence cognitive performance, particularly in older adults. One gene related to executive functioning is the COMT gene with met/met carriers outperforming val/val carriers in cognitive tasks. Further, it has been shown that fitness is positively related to cognitive functioning in older adults. As both, the COMT genotype and physical exercise have been shown to influence dopamine availability and as changes in dopamine metabolism seem to play a key role in cognitive aging, the aim of this study was to analyze the association of the COMT gene polymorphisms with the relationship between fitness and cognition.DesignWe used a cross-sectional design.MethodSixty-eight healthy older adults between 62 and 79 years of age were analyzed in this study. DNA was extracted from capillary blood samples. Participants performed a modified version of the Flanker Task as an indicator of executive control and a battery of motor and physical tests as indicators of fitness.ResultsHierarchical regression analyses revealed a positive influence of overall fitness and an interactive effect of fitness and COMT polymorphisms on Flanker accuracy performance. Val/val carriers revealed the highest positive correlation between fitness and cognition.ConclusionsOur data suggest that particularly val/val allele carriers benefit from exercise by improved cognitive functioning whereas met/met carriers already perform closer at their optimum level.     

Elucidating the Relation of Hoarding to Obsessive Compulsive Disorder and Impulse Control Disorders

Hoarding has historically been conceptualized as a symptom of Obsessive Compulsive Disorder (OCD); however, data demonstrate important differences between hoarding and OC symptoms (for discussion, see Grisham et al. Anxiety Disorders, 19, 767‑779. 2005). Hoarding has also been observed in disorders besides OCD, including specific Impulse Control Disorders (ICDs; e.g., kleptomania, trichotillomania, pathological gambling, compulsive buying). Therefore, the current study tested the hypothesis that hoarding would be as strongly related to symptoms of ICDs as it is to OCD and that these relationships would be medium to strong in magnitude. Results from an undergraduate sample showed hoarding behaviors were strongly related to symptoms of OCD, moderately related to symptoms of compulsive buying, and more modestly related to symptoms of pathological gambling, trichotillomania, and kleptomania. Finally, findings suggest indecisiveness may be a particularly important underlying feature in hoarding behaviors. These results support the consideration of hoarding outside the confines of OCD.

Deconstructing executive deficits among persons with autism: implications for cognitive neuroscience

Individuals with autism demonstrate impairments on measures of executive function (EF) relative to typically developing comparison participants. EF is comprised of several processes including inhibition, working memory and set shifting that develop throughout the lifespan. Impairments in EF may appear early in development and persist, or may represent a more transient delay which resolves with time. Given the unevenness of the cognitive profile of persons with autism, understanding the development of EF poses methodological challenges. These issues include those related to matching measures and the choice of comparison participants to which the performance of persons with autism will be compared. In the current review, we attempt to break down the processes of inhibition, working memory and set shifting among persons with autism. We propose to do this within a developmental perspective that highlights how matching measures and comparison participants can affect the interpretation of research findings.     

Categorization and sensorimotor interaction with objects

Three experiments were aimed at verifying whether the modality of interaction with objects and the goals defined by the task influences the weight of the properties used for categorization. In Experiment 1 we used everyday objects (cups and glasses). In order to exclude that the results depended on pre-stored categorical knowledge and to assess the role of a purely perceptual property such as colour, novel objects were used respectively in Experiment 2 and Experiment 3. Participants experienced objects in different modalities of interaction: Vision, Vision+Action, Action, and Mirror (they observed an experimenter touching and lifting them), then they were submitted to a similarity evaluation task and to a more action-based sorting task. Objects varied in intrinsic properties which had a different degree of interactivity: Grip, Shape, Size and Colour. Overall Grip, the most interactive property, was relevant for categorization, together with Size in Experiment 1 and with Shape in Experiment 2 and Experiment 3. The relevance of Grip in the sorting task confirms that goal-relevant properties are more weighted. The absence of a modality effect is discussed in the framework of the theories arguing that the vision of objects and of conspecifics interacting with objects automatically activates motor information.     

Categorization by groups and individuals

Categorization is a core psychological process that is central to decision making. While a substantial amount of research has been conducted to examine individual categorization behavior, little is known about how the outputs of individual and group categorization may differ. Four experiments demonstrate that group categorization differs systematically from individual categorization in the structural dimension of category breadth: categorizing the same set of items, groups tend to create a larger number of smaller categories than individuals. This effect of social context is a function of both taskwork and teamwork. In terms of taskwork, groups’ greater available knowledge mediates differences in category breadth between individuals and groups by increasing utilized knowledge (study 2). In terms of teamwork, task conflict moderates the effect of social context on category breadth (study 3). Moreover, the experience of categorizing individually or in a group influences individuals’ subsequent judgments (study 4).     

Conferring humanness: The role of anthropomorphism in hoarding

Hoarding is characterized by a persistent and extreme difficulty with discarding one’s possessions, often resulting in cluttered living spaces and marked distress or impairment. Despite being increasingly recognized as a substantial public health burden, much remains unknown about the etiology. One facet within the cognitive-behavioral model of hoarding that remains poorly understood is the strong emotional attachment to possessions. The tendency to anthropomorphize (i.e., see human-like qualities in non-human entities) may be one possible mechanism contributing to this emotional attachment. The current report is the first empirical study to examine the association between anthropomorphism and hoarding. Non-clinical participants (n = 72) completed a battery of self-report measures focused on hoarding symptoms, saving cognitions, anthropomorphism, and emotional attachments to personal and novel items. Anthropomorphic tendencies were significantly associated with greater saving behaviors and the acquisition of free things. Levels of anthropomorphism moderated the relationship between specific hoarding beliefs and acquiring tendencies, as well as the emotional attachment towards a novel item. Results are discussed with regard to future research directions, and implications for the cognitive-behavioral model of hoarding.     

Categorization of visual stimuli in the honeybee Apis mellifera

Categorization refers to the classification of perceptual input into defined functional groups. We present and discuss evidence suggesting that stimulus categorization can also be found in an invertebrate, the honeybee Apis mellifera, thus underlining the generality across species of this cognitive process. Honeybees show positive transfer of appropriate responding from a trained to a novel set of visual stimuli. Such a transfer was demonstrated for specific isolated features such as symmetry or orientation, but also for assemblies (layouts) of features. Although transfer from training to novel stimuli can be achieved by stimulus generalization of the training stimuli, most of these transfer tests involved clearly distinguishable stimuli for which generalization would be reduced. Though in most cases specific experimental controls such as stimulus balance and discriminability are still required, it seems appropriate to characterize the performance of honeybees as reflecting categorization. Further experiments should address the issue of which categorization theory accounts better for the visual performances of honeybees.This contribution is part of the special issue “Animal Logics” (Watanabe and Huber 2006).     

Categorization and affect: evidence for intra-hemispheric interactions

Both emotional reactivity and categorization have long been studied within the framework of hemispheric asymmetry. However, little attempt has been made to integrate both research areas using any form of neuropsychological research, despite behavioral data suggesting a consistent relationship between affective and categorization processes. The primary goal of the current study was to examine the possibility of a laterally mediated interaction between emotional reactivity and the cognitive process of categorization. Using a split visual fields categorization task combined with affect inducing procedures, we hypothesized that the relationship between state affect and categorization would be dependent on the nature of state affect and on the hemisphere targeted. Results offered support for this hypothesis, showing that state affect related changes in categorization appeared only in the hemisphere commonly associated with both a specific affective state and categorization strategy employed. Findings are discussed in terms of possible evidence for a hemispheric arousal effect underlying the relationship between affect and categorization.     

A preliminary investigation of sex differences in associations between emotion regulation difficulties and higher-order cognitive abilities

The present study sought to clarify the cognitive correlates of emotion regulation difficulties (ERD). Further, because prior evidence suggests sex differences in emotion regulation, sex was examined as a moderator of associations between cognitive abilities and ERD. Participants (N = 154) completed self-report measures of ERD, and were administered neuropsychological tests assessing crystallized and fluid intelligence, as well as various components of executive functioning. Bivariate correlations and results from regression analyses suggested sex-dependent associations among cognitive processes and ERD. For men, inhibition of dominant response tendencies was associated with lower ERD, whereas for women, a host of executive abilities (e.g., greater inhibition, cognitive flexibility, semantic processing, abstract reasoning) were associated with greater ERD. Implications for the neurocognitive conceptualization of emotion dysregulation will be discussed.     

Categorization by schema relations and perceptual similarity in 5-year-olds and adults: A study in vision and in audition

This research explores the way in which young children (5 years of age) and adults use perceptual and conceptual cues for categorizing objects processed by vision or by audition. Three experiments were carried out using forced-choice categorization tasks that allowed responses based on taxonomic relations (e.g., vehicles) or on schema category relations (e.g., vehicles that can be seen on the road). In Experiment 1 (visual modality), prominent responses based on conceptually close objects (e.g., objects included in a schema category) were observed. These responses were also favored when within-category objects were perceptually similar. In Experiment 2 (auditory modality), schema category responses depended on age and were influenced by both within- and between-category perceptual similarity relations. Experiment 3 examined whether these results could be explained in terms of sensory modality specializations or rather in terms of information processing constraints (sequential vs. simultaneous processing).     

Categorization of two-dimensional and three-dimensional stimuli by 18-month-old infants

In two experiments, 18-month-old infants’ categorization of 3D replicas and 2D photographs of the same animals and vehicles were compared to explore infants’ flexibility in categorization across different object representations. Using a sequential touching procedure, infants completed one superordinate and two basic-level categorization tasks with 3D replicas, 2D cut out photographs, or 2D images on photo cubes (“2D cubes”). For superordinate sets, 3D replicas elicited longer mean run lengths than 2D cut outs, and 3D replicas elicited equivalent mean run lengths as 2D cubes. For basic-level sets, infants categorized high-contrast animal sets when presented with 3D replicas, but they failed to categorize any of the 2D photograph sets. Categorization processes appear to differ for 3D and 2D stimuli, and infants’ discovery of object properties over time while manipulating objects may facilitate categorization, as least at the superordinate level. These findings are discussed in the context of infants’ representation abilities and the integration of perception and action.