Disentangling cognitive flexibility: a model-based assessment of women with anorexia nervosa.

Cognitive flexibility (CF) has been proposed as a potential trait marker in anorexia nervosa (AN), although findings have been inconsistent. To address this inconsistency, we applied a model that distinguishes between three subtypes of CF: task switching, switching sets, and stimulus-response mapping, which we then assessed using a paradigm-based task battery. The aim of the study was to investigate how AN is associated with these three CF subtypes. Thirty-three women with AN and 37 age- and education-matched controls performed a battery of computerized cognitive tasks to assess the three CF subtypes. Compared to the control group, individuals with AN exhibited poorer performance on the task switching and switching sets subtypes, as measured by response time switch cost, but not on the stimulus-response mapping subtype. No differences were found between the groups in response accuracy. Furthermore, switching sets as compared to the task switching and stimulus-response mapping subtypes was found to better explain the differences between the groups. These findings indicate a domain-specific impairment in CF among patients with AN, reflecting deficits observed in subtypes related to the disorder's characteristics, particularly that associated with visual perception. Therefore, CF impairment in AN should not be viewed dichotomously, but rather as a relative impairment that varies depending on the specific CF subtype.

Determinants of Quality of Life in Individuals With Spinal Cord Injury Using Structural Equation Modeling.

OBJECTIVE: The objective of this study is to examine the interdependent associations between International Classification of Functioning, Disability and Health (ICF) domains and their relationship with environmental factors with regard to quality of life (QoL) in individuals with spinal cord injury (SCI). DESIGN: Survey, cross-sectional study, and model testing using structural equation modeling. SETTING: Two inpatient and outpatient SCI rehabilitation units, Sheba Medical Center and Loewenstein Hospital, Israel. PARTICIPANTS: Convenience sample of 156 individuals with SCI (N=156). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: QoL assessed by the World Health Organization Quality of Life Assessment-BREF. Neurological impairment after SCI reflected by lesion completeness and neurologic level of injury as measured by the International Standards for Neurological Classification of Spinal Cord Injury. The Spinal Cord Independence Measure to assess SCI-related task performance. ICF Brief Core Sets composition scores to assess impairment in body structure and function domains, limitations in activities, restriction in participation constructs, and the effect of environmental factors within the ICF model. RESULTS: Level of spinal cord injury and ICF Brief Core Sets composite score relating to activities and participation construct demonstrated a direct significant association with QoL. Moreover, a significant indirect association with QoL was found between the composite scores in ICF body structure and function and environmental factors, level of spinal cord injury, time since injury onset, and sex. Because the Spinal Cord Independence Measure was not related to QoL, we inferred that the categories related to instrumental activities of daily living and participation exert the most significant influence on QoL. CONCLUSIONS: In order to optimize improvements in quality of life, current rehabilitation programs should target limitations specifically related to instrumental activities of daily living and participation restrictions. It may serve as a focal point for further development of current therapeutic models and analytical methods that optimize rehabilitation planning and decision making among both health care professionals and patients.

Working memory development in different modalities in children and young adults.

Research on working memory (WM) development is concentrated largely on the verbal and visuospatial domains, whereas the tactile modality has received much less attention. The current study aimed to compare the development of storage and manipulation in the tactile sense with other modalities in children and young adults. A total of 96 typically developed individuals were divided into three equally numbered age groups in the ranges of 7 and 8, 11 and 12, and 20 to 29 years. They were asked to perform a battery of span tasks, including forward and backward stages, in the verbal, visual, visuospatial, and tactile modalities. Results showed improvement of WM performance across age in all modalities. In addition, in the forward stage, the Tactual Span was shorter than all other tasks and the Visuospatial Span was shorter than the Visual-Digit Span. In the backward stage, the Digit Span and Tactual Span had lower scores than the Visuospatial Span. Finally, interaction effects for the forward and backward stages were also significant, mainly indicating greater improvement in both storage and manipulation of the tactile sense compared with the other senses. It can be concluded that the tactile modality shows a course of WM development similar to the other modalities, in all of which the storage and manipulation components are affected differently. In addition, tactile WM improves more during growth than other modalities. Therefore, professionals in the field of education and neuropsychology are encouraged to use tactile tasks to assess and treat WM, particularly in response to the increased use of digital technology during recent years.

Deductive Reasoning and Working Memory Skills in Individuals with Blindness.

Deductive reasoning and working memory are integral parts of executive functioning and are important skills for blind people in everyday life. Despite the importance of these skills, the influence of visual experience on reasoning and working memory skills, as well as on the relationship between these, is unknown. In this study, fifteen participants with congenital blindness (CB), fifteen with late blindness (LB), fifteen sighted blindfolded controls (SbfC), and fifteen sighted participants performed two tasks of deductive reasoning and two of working memory. We found that while the CB and LB participants did not differ in their deductive reasoning abilities, the CB group performed worse than the sighted controls, and the LB group performed better than the SbfC group. Those with CB outperformed all the other groups in both of the working memory tests. Working memory is associated with deductive reasoning in all three visually impaired groups, but not in the sighted group. These findings suggest that deductive reasoning is not a uniform skill, and that it is associated with visual impairment onset, the level of reasoning difficulty, and the degree of working memory load.

Visuospatial and Tactile Working Memory in Individuals with Congenital Deafness.

Studies examining visuospatial working memory (WM) in individuals with congenital deafness have yielded inconsistent results, and tactile WM has rarely been examined. The current study examined WM span tasks in the two modalities among 20 individuals with congenital deafness and 20 participants with typical hearing. The congenital deafness group had longer forward and backward spans than typical hearing participants in a computerized Corsi block-tapping test (Visuospatial Span), whereas no such difference was found in the Tactual Span (tactile WM). In the congenital deafness group, age of sign language acquisition was not correlated with either condition of the visuospatial task, and Tactual and Visuospatial Spans scores were correlated in the backward but not the forward condition. The typical hearing group showed no correlation between the tasks. The findings suggest that early deafness leads to visuospatial but not tactile superiority in WM, specifically with respect to the storage component. More broadly, it appears that deafness-related compensation mechanisms in WM do not affect the other modalities in a uniform manner.

Executive functioning and spatial processing in anorexia nervosa: an experimental study and its significance for the allocentric lock theory.

PURPOSE: The allocentric lock theory (ALT) suggests that people with eating disorders have difficulties in multisensory integration in two reference frames-egocentric and allocentric, whereby the egocentric, but not allocentric, is impaired. This leads to a distorted body image that contributes to the development and maintenance of the disorder. The current study aimed to explore a facet of the ALT, namely, the visuo-spatial aspect, and its relation to cognitive flexibility in patients with anorexia nervosa (AN). METHODS: Fifty-five participants took part in the study: 20 AN patients and 35 controls, matched by age and education. The object perspective taking test (OPTT) and the mental rotation test (MRT), tapping egocentric and allocentric representations, respectively, and a set-shifting task were administered. The brief symptom inventory was used to measure overall levels of distress. RESULTS: AN patients showed higher level of distress. They performed poorer on the OPTT and set-shifting task but not on the MRT. The OPTT and MRT were correlated for controls but not for AN patients, while the set-shifting task and body mass index were associated with the OPTT but not with the MRT for the AN patients. CONCLUSIONS: The findings support the ALT by demonstrating impaired visual egocentric representations and intact allocentric visual functions in AN patients, with cognitive flexibility associated only with the egocentric frame. Therefore, egocentric frame impairment in AN patients may be influenced by visual perception and cognitive flexibility deficiency. LEVEL OF EVIDENCE: Level III: case-control analytic study.

Verbal Versus Figural Fluency Tests in Currently Ill and Weight Restored Anorexia Nervosa Patients.

Fluency tests allow domain-specific assessment of verbal and non-verbal executive functions (EF) comparison and also enable utilizing of both quantitative and qualitative scoring methods. Thirty-five currently ill anorexia nervosa patients (PANs), 33 weight-restored patients (WRAN) and 47 healthy controls (HCs) were administered the word fluency test and the five-point test. Results show that WRANs tended to perseverate more than HCs in the verbal-fluency test. In addition, PANs produced significantly less correct figures and perseverated more than HCs and WRANs; HCs used more strategy methods than PANs and WRANs. Additionally, a positive correlation was found in the HC group between the total number of words in the verbal phonemic test and the number of designs produced and the number of correct designs. No such correlations were found in both anorexia groups. In conclusion, there is a differentiation between verbal and non-verbal EF in PANs and WRANs, showing a deficiency in the non-verbal domain. These findings may contribute to our understanding of the cognitive nature of the disorder.

Persistent extreme regressive behavior in severe traumatic brain injury patients: a rare neurological phenomenon.

Regressive behavior is a known sequela after severe traumatic brain injury (TBI). However, prolonged "infantile-like" behavior has received little attention in the literature, suggesting that this is a rare phenomenon. It is typically characterized by long-lasting childish, extremely dependent, and sometimes aggressive behavior, which is distinguished from the expected recovery process. The relevant theoretical framework lies in the field of disorders called "Neuropathologies of the self" (NPS). We report three cases of young adults who, following a severe TBI, developed continual regressive behavior. The Disability Rating Scale (DRS) was used to assess possible change in their condition. First, while admitted, which was performed in retrospect, and again 6 years later at the time stated. Inter-rater reliability for the scale items showed adequate correlation. Results showed no significant difference in patients' scores, indicating persistent functional difficulties. We conclude that this "regressive syndrome" presents an unusual form of behavior that is stable over time. It seems to be in line with other NPS disorders, and may stem from an interaction of organic factors and primary mental complexity. Nevertheless, further research is required to examine the factors affecting the emergence and recovery from this phenomenon.

The sorting test of the D-KEFS in current and weight restored anorexia nervosa patients.

OBJECTIVE: Efforts have been made to characterize executive functions (EF) in anorexia nervosa (AN) both in the acute stage of the illness and after weight gain, yet many questions remain. The question of verbal versus visuo-perceptual stimuli in this regard has not been adequately addressed. The aim of this study is to further examine EF in women with past and present AN and to compare their performances in verbal and visual modalities with women who have never suffered from an eating disorder. METHOD: Thirty-five underweight AN patients, 33 weight-restored patients symptom-free for at least 2 years, and 48 healthy female controls completed the Delis-Kaplan Executive Function System Sorting Test, so as to evaluate their EF. RESULTS: No differences were observed between the scores of women with current and past AN. Both groups scored lower than controls on most test variables. However, while in the visuo-perceptual domain the performance of the AN groups was worse than that of controls, in the verbal domain they performed similarly to them. DISCUSSION: Women with a past or present diagnosis of AN show difficulties in visuo-perceptual EF, whereas verbal EF seem to be preserved. There may be a dissociation between verbal and visuo-perceptual EF that persists after weight restoration.

Employing executive functions of perceptual and memory abilities in underweight and weight-restored anorexia nervosa patients.

PURPOSE: Executive functions (EF) have been widely investigated in anorexia nervosa (AN) revealing difficulties in various aspects. We aimed at testing the effects of EF on stimuli perception and its representations in memory. METHODS: Thirty AN underweight patients, 30 weight-restored AN patients, and 44 control participants, were recruited. Various EF were assessed using the Rey-Osterrieth Complex Figure Test, analyzed with the Boston Qualitative Scoring System. RESULTS: No differences were found in visuo-constructional measures in either AN groups compared to controls on the copy and memory stages. However, both groups performed significantly worse than controls on most EF variables in the copy stage, while in the immediate and delayed memory stages the difference was less substantial. CONCLUSIONS: Difficulties in EF among AN patients, current and weight restored, are more pronounced in the perceptual module and less so when employed through memory retrieval. The pattern, which is apparent after weight gain, suggests that there is no ameliorative effect on these difficulties.