Executive Functioning and Speed of Processing in Phenylketonuria.

Treated phenylketonuria (PKU) has been linked to dopaminergic depletion in the dorsolateral prefrontal cortex, potentially leading to selective executive impairment. White matter abnormalities may lead to generalized slowing of information processing. These 2 hypotheses were evaluated in adults with PKU on a lifelong diet. Those with PKU were significantly slower than the control group regardless of working memory load on an n-back task and marginally slower regardless of trial type (inhibitory or noninhibitory) on a flanker task. There were no significant differences in speed on object alternation learning or perceptual judgment tasks. There were no group differences in accuracy on any task. These findings do not appear consistent with the selective executive hypothesis. A cognitive slowing account may prove more informative in adults with PKU, but more evidence is needed. The findings suggest that continuous dietary management is a fairly successful strategy in terms of cognitive outcome for adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Is dual-task slowing instruction dependent?

When 2 tasks must be performed concurrently, each requiring a choice of response, dual-task slowing is typically found. However, E. H. Schumacher et al. (1997) reported that dual-task slowing can be eliminated when equal priority is assigned to each task. Experiment 1 largely confirmed this with the same tasks as Schumacher et al. (tasks using stimulus–response combinations of visual–manual and auditory–vocal pairings). Experiment 2 retained the equal-priority instructions but switched the task pairings (to visual–vocal and auditory–manual); substantial dual-task slowing occurred. Experiment 3 used the same two response sets but only a single stimulus; slowing was again obtained despite equal priority instructions. Equalizing task priority was not sufficient to eliminate interference; relatively unusual cases in which dual-task interference is eliminated seem to depend on task-specific features. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Timing is everything: Executive functions in children exposed to elevated levels of phenylalanine.

This study addresses how the timing of a known biological insult affects the developmental progression of executive functions. The sample consisted of children exposed to elevated levels of phenylalanine, either postnatally, as in phenylketonuria (PKU; n = 46), or prenatally, as in maternal PKU (n = 15). Nonhyperphenylalaninemic siblings of children with PKU (n = 18) served as controls. Results indicated that elevated levels of phenylalanine are toxic to the neurological systems that manage executive functions and cognitive tempo. This toxicity is dose dependent, with higher levels of phenylalanine being more detrimental. Executive function difficulties noted in PKU are consistent with attention deficit hyperactivity disorder (ADHD)-inattentive type, whereas maternal PKU offspring had executive function difficulties consistent with ADHD-combined type. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Characterizing executive functioning in older special populations: From cognitively elite to cognitively impaired.

The authors examined the structure and invariance of executive functions (EF) across (a) a continuum of cognitive status in 3 groups of older adults (cognitively elite [CE], cognitively normal [CN], and cognitively impaired [CI]) and (b) a 3-year longitudinal interval. Using latent variable analyses (LISREL 8.80), the authors tested 3-factor models (“Inhibition”: Hayling [Burgess & Shallice, 1997], Stroop [Regard, 1981]; “Shifting”: Brixton [Burgess & Shallice, 1997], Color Trails [D’Elia et al., 1996]; and “Updating”: Reading and Computational Span [Salthouse & Babcock, 1991]) and 1-factor models within each group. Participants (initial N = 570; 53–90 years) were from the Victoria Longitudinal Study (Sample 3, Waves 1 and 2). Cross-sectionally, the authors observed a 3-factor EF structure especially for the CE group and 1-factor solutions for all 3 groups. Longitudinally, temporal invariance was supported for the 3-factor model (CE and CN groups) and the 1-factor model (CI and CN groups). Subgroups with higher cognitive status and greater 3-year stability performed better on EF factors than corresponding groups with lower cognitive status and less stability. Studies of EF structure, performance, dedifferentiation, and dysfunction will benefit from considering initial cognitive status and longitudinal stability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Deficits in memory strategy use related to prefrontal dysfunction during early development: Evidence from children with phenylketonuria.

The prefrontal cortex has been implicated in the mediation of executive processes that facilitate learning and memory. The authors hypothesized that children with prefrontal dysfunction related to phenylketonuria (PKU) would experience deficits in learning and memory because of impaired strategy use. They evaluated 23 children with PKU and 23 controls by using the California Verbal Learning Test-Children's Version (CVLT-C). General executive abilities were tested using the Stroop Color and Word Test, the Wisconsin Card Sorting Test, and phonemic and category fluency. Children with PKU, especially older children, showed poorer learning across trials and less use of semantic clustering on the CVLT-C but intact retention of previously encoded information. With the exception of phonemic fluency, deficits were not observed in general executive control. Results are discussed within the context of abnormalities in the prefrontal cortex and white matter of the brain. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of placement instability on adopted children's inhibitory control abilities and oppositional behavior.

This study assessed relations among placement instability, inhibitory control, and caregiver-rated child behavior. The sample included 33 adopted children who had experienced placement instability, 42 adopted children who had experienced 1 stable placement, and 27 children never placed in foster care. Five- and 6-year-old children completed the day-night task, which requires children to inhibit a prepotent response, and a control task that presents similar memory demands but does not require inhibition (C. L. Gerstadt, Y. J. Hong, & A. Diamond, 1994). Adopted children who had experienced placement instability performed worse on the inhibition task than did both other groups of children, when the authors controlled for age, verbal intelligence (as measured with the Wechsler Preschool and Primary Scale of Intelligence--Revised; D. Wechsler, 1989; or the Peabody Picture Vocabulary Test--Third Edition; L. M. Dunn & L. M. Dunn, 1997), and control task performance (p.05). These results suggest that placement instability may adversely affect the social-emotional development of adopted children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prevention of infective endocarditis in the pediatric congenital heart population

In 1997, the American Heart Association updated recommendations for the prevention of sub-acute bacterial endocarditis (SBE) or infective endocarditis (IE) occurring in the pediatric population with congenital heart disease (Dajani, et al., 1997). Although uncommon, endocarditis remains an important cause of morbidity and mortality in children with cardiovascular disease, which constitutes the primary population at risk. Through comprehensive discharge planning and teaching, the advanced practice nurse (APN) and the pediatric cardiovascular nurse may contribute significantly toward preventing IE in this population. Nursing's role and responsibility is to convey the appropriate information to patients, families, and the staff who care for children with heart disease.     

Executive Functioning, Memory, and Learning in Phenylketonuria.

The executive deficit hypothesis of treated phenylketonuria (PKU) suggests that dopaminergic depletion in the lateral prefrontal cortex leads to selective executive impairment. This was examined by comparing adults with PKU on a lifelong diet with a matched healthy control group. Those with PKU were impaired on selective and sustained attention, working memory (Self-Ordered Pointing), and letter fluency. However, they failed to show differential sensitivity to increased cognitive load on the attentional and working memory tasks, and they did not differ significantly on the remaining executive tasks (rule finding, inhibition, and multitasking). Nor did they differ significantly on recall or recognition memory. Overall, the findings provided little support for the executive deficit hypothesis. A possible explanation in terms of slowed information processing speed is explored. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive functions and the antioxidant system in phenylketonuric patients.

The authors studied the relationship between the antioxidant system and cognitive functions in a group of 36 early and continuously treated phenylketonuric (PKU) patients (mean age=9.7 years) and 29 controls. The authors measured antioxidant cofactors and free radical damage markers in plasma (selenium, retinol, tocopherol, coenzyme Q10, malondialdehide) and antioxidant enzymes in red blood cells (glutathione peroxidase, catalase, superoxide dismutase). The authors used neuropsychological tests to screen for several cognitive functions. PKU patients showed significantly lower values of selenium, coenzyme Q10, and catalase, and significantly higher levels of malondialdehide. PKU patients showed a significantly negative correlation between plasma selenium concentrations and several Conner's Continuous Performance Test measures (more omission errors, fluctuating attention and inconsistency of response times, and slowing reaction time as the test progressed). Selenium deficiency was thus associated with a worsened performance on the Conner's Continuous Performance Test among PKU patients. In conclusion, it is important not only to control blood Phe levels in PKU but also other nutritional components such as selenium. Selenium status seems to be associated with attention functions in these PKU patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social relationships and negative emotional traits are associated with central adiposity and arterial stiffness in healthy adolescents.

Objective: We examined the role of social relationships and negative emotional traits in the development of central adiposity and arterial stiffness in healthy adolescents. Design: A prospective, longitudinal study examined 213 Black and White adolescents (50% Black, 51% female); 160 returned for a second assessment approximately 3 years later. Main Outcome Measures: Psychosocial variables at both assessments were measured with the Measurement of Attachment Qualities (Carver, 1997), Social Relationships Index (study entry only; Uchino, Holt-Lunstad, Uno, & Flinders, 2001), Spielberger Trait Anger and Anxiety (Spielberger et al., 1979), and the Cook–Medley Hostility Scale (Cook & Medley, 1954). Central adiposity was assessed by waist-to-hip ratio (WHR) at both assessments and arterial stiffness by pulse wave velocity (PWV) at the second assessment only. Results: Linear regression models controlled for demographic variables and body mass index showed that adolescents with less Supportive Relationships (β = ?.121, p = .05) and higher Trait Anger (β = .117, p = .05) had increased WHR over time, adjusted for initial WHR. Those with higher Attachment Anxiety (β = .211, p = .01) and Total Hostility (β = .234, p     

Executive function in parents of children with autism

BACKGROUND: Previous studies have shown that individuals with autism show impaired performance on tests of executive function (Ozonoff et al. 1991, 1993; Hughes & Russell, 1993; Hughes et al. 1994). There is also strong evidence for genetic involvement in autism (see Rutter, 1991 for review). If executive dysfunction is a core impairment in autism, then similar impairments are hypothesized to exist in a subtler form among the parents of autistic children. METHODS: Forty parents of autistic children were compared with 40 parents of learning disabled children and 36 adults from unaffected families on three computerized tests of executive function. These tasks tapped attentional-shifting skills, visuospatial planning and working memory. Participants also received a computerized control test of spatial memory-span. In addition, the interviewer's initial impressions of family members were coded using a new 33-item questionnaire. RESULTS: A significant proportion of parents of autistic children (especially fathers) showed impaired executive function. By contrast, parents did as well as both comparison groups on a control test of spatial span, and on other 'non-executive' measures from the tasks, indicating that the autism group were as able and motivated as comparison groups. Interestingly, impairment of executive function was significantly correlated with the interviewer's pre-test impression of social abnormality among parents of autistic children. CONCLUSIONS: The hypothesis that a significant proportion of parents of autistic children show impaired executive function was supported. Parents showed good memory ability, but relatively poor planning skills and attentional flexibility. The extent to which this is an inherent trait in family members, rather than a reflection of the difficulties involved in caring for an autistic child, remains to be examined.     

Notes on lifelong resilience. Perceptual and personality factors implicit in the creation of a particular adaptive style.

Resilience in children has conventionally been defined as the capacity to negotiate ordinary developmental tasks successfully in spite of cumulative adversity (P. Fonagy et al., 1994; A. S. Masten et al., 1999; H. Stein et al., 2000; E. Werner & R. S. Smith, 1992). It has been attributed in part to the presence of "protective factors" in the child or in the environment (M. Rutter, 1985). The case of "Rita," a young African American woman, is presented as an example of a person who developed extraordinary resilience as a child in the face of chronic abuse. She was able to create sustaining relationships in the "safe space" (J. Sandler, 1960) she achieved through the use of eye contact. The way she put eye contact to use to develop resilience is explored by means of attachment and psychoanalytic theory. Finally, her work in psychoanalytically oriented psychotherapy is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential stimulation of c-fos expression in hypothalamic nuclei of the rat brain during short-term heat acclimation and mild dehydration

Evidence that multiple, probably non-endocytic mechanisms are involved in the uptake into mammalian cells of the alpha-helical amphipathic model peptide FLUOS-KLALKLALKALKAALKLA-NH2 (I) is presented. Extensive cellular uptake of N-terminally GC-elongated derivatives of I, conjugated by disufide bridges to differently charged peptides, indicated that I-like model peptides might serve as vectors for intracellular delivery of polar bioactive compounds. The mode of the cellular internalization of I comprising energy-, temperature-, pH- and ion-dependent as well as -independent processes suggests analogy to that displayed by small unstructured peptides reported previously (Oehlke et al., Biochim. Biophys. Acta 1330 (1997) 50-60). The uptake behavior of I also showed analogy to that of several protein-derived helical peptide sequences, recently found to be capable of efficiently carrying tagged oligonucleotides and peptides directly into the cytosol of mammalian cells (Derossi et al., J. Biol. Chem. 269 (1994) 10444-10450; Lin et al., J. Biol. Chem. 270 (1995) 14255-14258; Fawell et al., Proc. Natl. Acad. Sci. USA 91 (1994) 664-668; Chaloin et al., Biochemistry 36 (1997) 11179-11187; Vives et al., J. Biol. Chem., 272 (1997) 16010-16017).     

Complementary/alternative medicine for asthma: we do not know what we need to know

In a recent report, a series of studies is described showing that individual differences in rat maternal licking and grooming are correlated with their offsprings' later adrenal response to a stressor (Liu et al., 1997). Pups that received more maternal stimulation in infancy had lower ACTH, corticosterone, and CRH mRNA, while they had greater amounts of GR mRNA. Liu et al. also compared maternal behavior in litters where rat pups were handled daily to maternal behavior of nonhandled litters. They found that mothers of handled pups licked and groomed their young significantly more often than did mothers of control litters. In their discussion, Liu et al. proposed that their data support Levine's (1975) thesis that handling effects in infancy are mediated via the mother. Levine had proposed that handling of pups will modify the mother--pup interaction, thereby causing a change in maternal behavior. The purpose of this commentary is to summarize data obtained with mice and rabbits which, in part, support and, in part, challenge the conclusions of Liu et al.     

On dimensionality, discriminant validity, and the role of psychometric analyses in personality theory and measurement: Reply to Kruglanski et al.'s (1997) defense of the Need for Closure Scale.

D. M. Webster and A. W. Kruglanski's (1994) Need for Closure Scale (NFCS) confounds multiple dimensions and is redundant with existing instruments (S. L. Neuberg, T. N. Judice, & S. G. West, 1997). A. W. Kruglanski and his colleagues (1997) dismissed these findings as "psychometric naysaying," although they presented no data that refute them. Moreover, Kruglanski et al (1997) suggested that researchers (a) be unconcerned with the NFCS's lack of discriminant validity and (b) use the scale as if it were unidimensional. These recommendations are problematic. Using the NFCS in this manner invites interpretational ambiguity and theoretical confusion. In contrast to the Kruglanski et al (1997) position, proper psychometric analyses play a critical role in theory testing and in the development of conceptually coherent measures of individual differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive functioning ten years following traumatic brain injury and rehabilitation.

Many previous studies investigating long-term cognitive impairments following traumatic brain injury (TBI) have focused on extremely severely injured patients, relied on subjective reports of change and failed to use demographically relevant control data. The aim of this study was to investigate cognitive impairments 10 years following TBI and their association with injury severity. Sixty TBI and 43 control participants were assessed on tests of attention, processing speed, memory, and executive function. The TBI group demonstrated significant cognitive impairment on measures of processing speed (Symbol Digit Modalities Test [SDMT], Smith, 1973; Digit Symbol Coding, Wechsler, 1997), memory (Rey Auditory Verbal Learning Test [RAVLT]; Rey, 1958; Lezak, 1976), Doors and People tests; Baddeley, Emslie & Nimmo-Smith, 1994) and executive function (Hayling C [Burgess & Shallice, 1997] and SART errors, Robertson, Manly, Andrade, Baddeley & Yiend, 1997). Logistic Regression analyses indicated that the SDMT, Rey AVLT and Hayling C and SART errors most strongly differentiated the groups in the domains of attention/processing speed, memory and executive function, respectively. Greater injury severity was significantly correlated with poorer test performances across all domains. This study shows that cognitive impairments are present many years following TBI and are associated with injury severity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Catastrophic misinterpretations as a predictor of symptom change during treatment for panic disorder.

Objective: Cognitive models of panic disorder suggest that change in catastrophic misinterpretations of bodily sensations will predict symptom reduction. To examine change processes, we used a repeated measures design to evaluate whether the trajectory of change in misinterpretations over the course of 12-week cognitive behavior therapy is related to the trajectory of change in a variety of panic-relevant outcomes. Method: Participants had a primary diagnosis of panic disorder (N = 43; 70% female; mean age = 40.14 years). Race or ethnicity was reported as 91% Caucasian, 5% African American, 2.3% biracial, and 2.3% “other.” Change in catastrophic misinterpretations (assessed with the Brief Body Sensations Interpretation Questionnaire; Clark et al., 1997) was used to predict a variety of treatment outcomes, including overall panic symptom severity (assessed with the Panic Disorder Severity Scale [PDSS]; Shear et al., 1997), panic attack frequency (assessed with the relevant PDSS item), panic-related distress/apprehension (assessed by a latent factor, including peak anxiety in response to a panic-relevant stressor—a straw breathing task), and avoidance (assessed by a latent factor, which included the Fear Questionnaire–Agoraphobic Avoidance subscale; Marks & Mathews, 1979). Results: Bivariate latent difference score modeling indicated that, as expected, change in catastrophic misinterpretations predicted subsequent reductions in overall symptom severity, panic attack frequency, distress/apprehension, and avoidance behavior. However, change in the various symptom domains was not typically a significant predictor of later interpretation change (except for the distress/apprehension factor). Conclusions: These results provide considerable support for the cognitive model of panic and speak to the temporal sequence of change processes during therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral expression of learned fear: Updating of early memories.

The expression of learned fear emerges in a response-specific sequence where freezing occurs before fear potentiated startle (FPS) to an odor conditioned stimulus (CS; Postnatal Day [PN] 16 vs. PN 23; e.g., Hunt, 1997; Richardson, Paxinos, & Lee, 2000). Studies have shown that learned fear is expressed in a manner appropriate to the animal's age at training and not its age at test (Richardson & Fan, 2002; Richardson et al., 2000). Specifically, animals trained with an odor CS at PN 16 exhibit avoidance but not FPS when tested at PN 23. The present study shows that subsequent training with a different CS can "update" an early memory, allowing it to be expressed in a manner appropriate to the animal's age at test. This updating effect appears to be modality specific, whereby the subsequent training must involve a CS of the same sensory modality as the original training. (PsycINFO Database Record (c) 2010 APA, all rights reserved)