Neuroanatomical and psychological considerations in temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is the most common form of focal epilepsy and is associated with a variety of structural and psychological alterations. Recently, there has been renewed interest in using brain tissue resected during epilepsy surgery, in particular 'non-epileptic' brain samples with normal histology that can be found alongside epileptic tissue in the same epileptic patients - with the aim being to study the normal human brain organization using a variety of methods. An important limitation is that different medical characteristics of the patients may modify the brain tissue. Thus, to better determine how 'normal' the resected tissue is, it is fundamental to know certain clinical, anatomical and psychological characteristics of the patients. Unfortunately, this information is frequently not fully available for the patient from which the resected tissue has been obtained - or is not fully appreciated by the neuroscientists analyzing the brain samples, who are not necessarily experts in epilepsy. In order to present the full picture of TLE in a way that would be accessible to multiple communities (e.g., basic researchers in neuroscience, neurologists, neurosurgeons and psychologists), we have reviewed 34 TLE patients, who were selected due to the availability of detailed clinical, anatomical, and psychological information for each of the patients. Our aim was to convey the full complexity of the disorder, its putative anatomical substrates, and the wide range of individual variability, with a view toward: (1) emphasizing the importance of considering critical patient information when using brain samples for basic research and (2) gaining a better understanding of normal and abnormal brain functioning. In agreement with a large number of previous reports, this study (1) reinforces the notion of substantial individual variability among epileptic patients, and (2) highlights the common but overlooked psychopathological alterations that occur even in patients who become "seizure-free" after surgery. The first point is based on pre- and post-surgical comparisons of patients with hippocampal sclerosis and patients with normal-looking hippocampus in neuropsychological evaluations. The second emerges from our extensive battery of personality and projective tests, in a two-way comparison of these two types of patients with regard to pre- and post-surgical performance.

Verbal working memory and processing speed: Correlations with the severity of attention deficit and emotional dysregulation in adult ADHD

Objectives

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM‐5), emphasizes symptoms severity with regard to the diagnosis of attention deficit hyperactivity disorder (ADHD). Many clinicians use neuropsychological test results as objective measures of cognitive functions as part of the diagnostic work‐up. The aim of this study was to investigate whether the psychometric test results regarding verbal working memory and processing speed are useful as indicators of the severity of attention deficits and emotional dysregulation in adults with ADHD.

Methods

This observational cross‐sectional clinical study included 418 adults diagnosed with ADHD according to the DSM‐5. Attention deficit severity was defined based on the inattentive subscale of the Adult ADHD Self‐Report Scale. Emotional dysregulation was assessed with the Deficient Emotional Self‐Regulation scale. Verbal working memory was measured with the Working Memory Index (WMI), and processing speed was measured with the Processing Speed Index (PSI) from the Wechsler Adult Intelligence Scale, third edition.

Results

The full‐scale intelligence quotients of the participants were in the normal range, with expected reductions in verbal working memory and processing speed. Only processing speed was associated with attention deficits (β = −.056, p = .003). The association between the psychometric test result for verbal working memory and processing speed and that between the severity of attention deficits and emotional dysregulation were weak (R² < .1) and mostly non‐significant.

Conclusion

The psychometric index scores for verbal working memory (WMI) and processing speed (PSI) seem to have limited utility as indicators of the severity of attention deficits and emotional dysregulation in adult ADHD patients.

Effects of extended abstinence on cognitive functions in tramadol-dependent patients: A cohort study

BACKGROUND

Some pieces of the literature report impaired cognitive functioning in tramadol dependence. Whether extended abstinence improves cognitive functioning or not is not well studied.

AIM

We aimed to measure the change in cognitive functioning following complete abstinence among individuals with tramadol dependence.

METHODS

Eighty-three male tramadol-dependent (TD) and 57 matched healthy controls participated in this study. Cognitive functions were assessed using: The Trail making test (TMT), Wechsler Memory Scale-Revised (WMS-R), and Wechsler Adult Intelligence Scale (WAIS). Patients were assessed in the first week immediately after the end of the in-patient treatment program (T1), and after six months of sustained abstinence (T2).

RESULTS

At T1, the TD group showed deficits on all tested cognitive parameters (visual attention, task switching, working memory, visual memory, verbal memory, verbal knowledge, Verbal IQ, Performance IQ, and Full-Scale IQ) in comparison to the control group. At T2, significant improvements had occurred in all the tested parameters except performance IQ. The cognitive performance of the abstinent individuals at T2 was comparable to the control group for the verbal subsets of WMS-R, Verbal IQ, Performance IQ, and Full-Scale IQ. Nevertheless, it was still worse than the control group in TMT, and all other WMS subsets.

CONCLUSION

tramadol dependence has negative effects on cognitive performance, which improves with extended abstinence.

Verbal Short-Form FSIQ Estimations for Possible Use With Individuals With Motor and Visual Impairment or in Virtual Environments

OBJECTIVE

Abbreviated and virtual neuropsychological assessment practices are growing in popularity and viable alternatives to traditional testing methods are needed, especially in the face of global health concerns. This study generated and examined short form (SF) full-scale IQ (FSIQ) estimations, which lend themselves to virtual test administration.

METHODS

Archival data were procured from 318 concurrent cognitive evaluations at a university clinic. Twenty-six unique SF combinations, including dyads, triads, tetrads, and pentads, were created from Wechsler Adult Intelligence Scale, 4th edition (WAIS-IV) subtests within verbal comprehension and working memory indices due to these tests' ability to be administered without visual stimuli or psychomotor involvement.

RESULTS

Stepwise regression analyses revealed 9 SF combinations (i.e., 1 pentad, 3 tetrads, 2 triads, and 3 dyads) that significantly accounted for unique variance in FSIQ scores and provided good accuracy estimating FSIQ.

CONCLUSION

Results suggest the potential viability of verbal WAIS-IV SF FSIQ estimations for clinical use when assessing patients with motor or visual impairments, as well as performing tele-neuropsychological services.

Performance on the Wechsler Adult Intelligence Scale (WAIS) in Japanese patients with bipolar and major depressive disorders in euthymic and depressed states

AIM

This study aimed to examine the cognitive performance of patients with bipolar disorder (BD) stratified by illness phase compared to that of patients with major depressive disorder (MDD) and healthy controls.

METHODS

Participants were 139 patients with BD (55 euthymic and 84 depressed), 311 patients with MDD (88 euthymic and 223 depressed), and 386 healthy controls who underwent the Wechsler Adult Intelligence Scale-Revised or the Third Edition. They were non-elderly Japanese individuals with normal estimated premorbid intelligence quotient (IQ; >90), group-matched for age, sex, and premorbid IQ.

RESULTS

The depressed BD group showed significantly lower scores on verbal IQ, performance IQ, full-scale IQ, and three group indexes of perceptual organization, working memory, and processing speed when compared with healthy controls (all P < 0.001). All IQs and working memory index were also significantly lower than those of the depressed MDD group. The depressed MDD group scored significantly lower than controls in performance IQ (P < 0.001), full-scale IQ, and only in the index of processing speed (P < 0.001). The euthymic BD group scored significantly lower than controls in performance IQ (P = 0.004), whereas the euthymic MDD group scored significantly lower than controls only in processing speed (P = 0.030).

CONCLUSION

Patients with BD appear to have global and more intense cognitive impairments in depressed states compared with those with MDD whose impairments seem to be apparent only in processing speed in the Wechsler Adult Intelligence Scale. Attenuated impairments appear to exist in euthymic states of both patients.

Correlation Between the Wechsler Adult Intelligence Scale- 3 rd Edition Metrics and Brain Structure in Healthy Individuals: A Whole-Brain Magnetic Resonance Imaging Study

Background

The Wechsler Adult Intelligence Scale, 3^rd edition (WAIS-III) is widely used to evaluate the intelligence quotient (IQ). We aimed to investigate the correlation between the WAIS-III metrics and whole-brain structures using magnetic resonance imaging.

Methods

The participants were 266 healthy, right-handed individuals (age: 45.6 ± 12.9 years, 98 males and 168 females). IQs were evaluated using the WAIS-III and Japanese Adult Reading Test (JART). Voxel-based morphometry and diffusion tensor imaging were performed to analyze the correlation of the WAIS-III metrics and JART score with the gray matter volume and white matter integrity, respectively.

Results

The verbal IQ significantly and positively correlated with the left gyrus rectus and anterior cingulate gyrus, left posterior insula and planum polare, and left superior and middle frontal gyri volumes (p < 0.05, corrected). The verbal comprehension group index significantly and positively correlated with the left superior and middle frontal gyri, left gyrus rectus and anterior cingulate gyrus, and left middle frontal gyrus volumes, while the processing speed group index significantly and positively correlated with the bilateral various regional white matter fractional anisotropy values (p < 0.05, corrected). In contrast, the JART score showed no correlation with any brain structure.

Conclusion

These results suggested the neurostructural bases of the WAIS-III IQs and group indices in the brain of healthy individuals.

The Relationship Between the Striatal Dopaminergic Neuronal and Cognitive Function With Aging

Both cognitive function and striatal dopamine function decline by normal aging. However, the relationship among these three factors remains unclear. The aim of this study was to elucidate the association among age-related changes in the striatal dopamine transporter (DAT) and cognitive function in healthy subjects. The 30 healthy volunteers were enrolled in this research, the age ranged from 41 to 82 (64.5 ± 11.5, mean ± SD). All subjects were scanned with both T1-weighted magnetic resonance imaging (MRI) and ¹²³I-FP-CIT single-photon emission computed tomography (SPECT) images. The Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) was used to evaluate cognitive function. Six spherical regions of interest (ROI) using 10 mm in diameter on the caudate nucleus, anterior putamen and posterior putamen were manually drawn on MRI image which was applied onto SPECT image. The relationship between striatal occipital ratio (SOR) values and WAIS-III subscore were analyzed by multiple regression analysis. Subscores which was significant were further analyzed by path analyses. Full intelligence quotient (IQ), verbal IQ, verbal comprehension were all positively correlated with age-adjusted striatal DAT binding (P < 0.01). Multiple regression analyses revealed that the coding digit symbol correlated with all striatal regions except for the left caudate (P < 0.04). Picture completion and right caudate, similarities and left caudate also showed a positive correlation (P < 0.04). Path analysis found that the right caudate and picture completion; the left caudate and similarities were correlated independently from age, whereas the models of coding digit symbol were not significant. These results suggest that age-based individual diversity of striatal DAT binding was associated with verbal function, and the caudate nucleus plays an important role in this association.

Plasma levels of matrix metalloproteinase-9 (MMP-9) are associated with cognitive performance in patients with schizophrenia

Aim

Matrix metalloproteinase‐9 (MMP‐9) has been shown to modulate synaptic plasticity and may contribute to the pathophysiology of schizophrenia. This study investigated the peripheral levels of MMP‐9 and its association with cognitive functions in patients with schizophrenia to see the possible involvement of MMP‐9 in pathophysiology of schizophrenia, especially in cognitive decline.

Methods

We measured the plasma levels of MMP‐9 in 257 healthy controls and 249 patients with schizophrenia, including antipsychotic drug–free patients. We also explored the possible association between plasma MMP‐9 levels and cognitive performance in healthy controls and patients with schizophrenia using the Wechsler Adult Intelligence Scale, Third Edition (WAIS‐ III), the Wechsler Memory Scale‐Revised (WMS‐R), and the Rey Auditory Verbal Learning Test (AVLT).

Results

We found that the plasma levels of MMP‐9 were significantly higher in patients with schizophrenia, including antipsychotic drug–free patients, than in healthy controls. We found a significant negative association between plasma MMP‐9 levels and cognitive performance in controls and patients with schizophrenia.

Conclusion

Together, these convergent data suggest a possible biological mechanism for schizophrenia, whereby increased MMP‐9 levels are associated with cognitive impairment.

Plasma levels of MMP‐9 were significantly higher in patients with schizophrenia and significant negative association between plasma MMP‐9 levels and cognitive performance was observed in controls and patients with schizophrenia.

Examination of Wechsler adult Intelligence Scale-Fourth Edition short-form IQ estimations in an outpatient psychoeducational sample

OBJECTIVE

The Wechsler Adult Intelligence Scale, 4th edition (WAIS-IV) is a commonly utilized cognitive battery across many clinical settings. However, due to various patient variables, an abbreviated assessment of intellectual abilities, may be clinically advantageous to allow for a more thorough assessment of other cognitive domains. The current study represents an attempt to propose additional short-form IQ estimations in an outpatient clinical sample.

METHODS

We examined archival data from 318 concurrent psychological/psychoeducational evaluations performed within a university clinic (M_age = 28.67; 53.8% women). Thirty-six unique 4-subtest short-form IQ combinations were created to ensure that each WAIS-IV index score was represented by a single subtest.

RESULTS

Complete data for the ten core subtests and FSIQ were available for 192 cases. Stepwise regression analyses revealed three short-form combinations that significantly accounted for unique variance in true FSIQ scores in the final model (R² = .981, F[3, 188] = 3257.597, p < .001). Regression-based and prorated FSIQ estimates were calculated, and both methods revealed that approximately 70-75% of participants' FSIQ estimates fell within five Standard Score points of true FSIQ.

CONCLUSION

Results suggest the utility of three derived 4-subtest short-form IQ estimations for use within a clinical sample.

Clinical utility of WAIS-IV 'excessive decline from premorbid functioning' scores to detect invalid test performance following traumatic brain injury

Objective: Excessive Decline from Premorbid Functioning (EDPF), an atypical discrepancy between demographically predicted and obtained Wechsler Adult Intelligence Scale-4th Edition (WAIS-IV) scores, has been recently proposed as a potential embedded performance validity test (PVT). This study examined the clinical utility of EDPF scores to detect invalid test performance following traumatic brain injury (TBI).Methods: Participants were 194 U.S. military service members who completed neuropsychological testing on average 2.4 years (SD = 4.0) following uncomplicated mild, complicated mild, moderate, severe, or penetrating TBI (Age: M = 34.0, SD = 9.9). Using TBI severity and PVT performance (i.e., PVT Pass/Fail), participants were classified into three groups: Uncomplicated Mild TBI-PVT Fail (MTBI-Fail; n = 21), Uncomplicated Mild TBI-PVT Pass (MTBI-Pass; n = 94), and Complicated Mild to Severe/Penetrating TBI-PVT Pass (CM/STBI-Pass; n = 79). Seven EDPF measures were calculated by subtracting WAIS-IV obtained index scores from the demographically predicted scores from the Test of Premorbid Functioning (TOPF). Cutoff scores to detect invalid test performance were examined for each EDPF measure separately.Results: The MTBI-Fail group had higher scores than the MTBI-Pass and CM/STBI-Pass groups on five of the seven EDPF measures (p<.05). Overall, the EDPF measure using the Processing Speed Index (EDPF-PSI) was the most useful score to detect invalid test performance. However, sensitivity was only low to moderate depending on the cutoff score used.Conclusions: These findings provide support for the use of EDPF as an embedded PVT to be considered along with other performance validity data when administering the WAIS-IV.

Brain functional impairment in beta-thalassaemia: the cognitive profile in Italian neurologically asymptomatic adult patients in comparison to the reported literature

Cognitive involvement in beta-thalassaemia is strikingly controversial and poorly studied in adulthood. This multicentre prospective study investigated 74 adult neurologically-asymptomatic beta-thalassaemia patients (mean-age 34·5 ± 10·3 years; 53 transfusion-dependent [TDT], 21 non-transfusion dependent [NTDT]) and 45 healthy volunteers (mean-age 33·9 ± 10·7 years). Participants underwent testing with Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV), Brief Psychiatric Rating Scale (BPRS) and multiparametric brain 3T-magnetic resonance imaging (MRI) for parenchymal, vascular and iron content evaluation. Patients had lower Full-Scale Intelligence Quotient (FSIQ) than controls (75·5 ± 17·9 vs. 97·4 ± 18·1, P < 0·0001) even after correction for education level. Compared to TDT, NTDT showed a trend of higher FSIQ (P = 0·08) but a similar cognitive profile at WAIS-subtests. FSIQ correlated with total and indirect bilirubin (P < 0·0001 and P = 0·002, respectively); no correlation was found with splenectomy, intracranial MRI/magnetic resonance-angiography findings, brain tissue iron content or other disease-related clinical/laboratory/treatment data. FSIQ did not correlate with BPRS scores, although the latter were higher among patients (28·74 ± 3·1 vs. 27·29 ± 4·8, P = 0·01) mainly because of increased depression and anxiety levels. Occupation rate was higher among controls (84·4% vs. 64·9%, P = 0·004) and correlated with higher FSIQ (P = 0·001) and education level (P = 0·001). In conclusion, Italian adult beta-thalassaemia patients seem to present a characteristic cognitive profile impairment and an increased rate of psychological disorders with possible profound long-term socio-economic consequences.

Furthering the Understanding of Wechsler Adult Intelligence Scale-Fourth Edition Factor Structure in a Clinical Sample

The Wechsler Adult Intelligence Scale, Fourth Edition (WAIS-IV) is a commonly administered battery for assessing intellectual and cognitive abilities. Despite its popularity, construct validation studies primarily utilize the WAIS-IV normative sample rather than ecologically-valid clinical samples. The current study expands the literature on the validity of WAIS-IV by testing a bifactor model in such a sample. We examined archival data from 300 concurrent psychological evaluations performed at a university-based community clinic. Participants received the full WAIS-IV standard battery. Consistent with recent literature, confirmatory factor analyses (CFAs) favored a direct hierarchical model, where the g factor has a direct influence on WAIS-IV subtest performance and index scores explain only modest degrees of residual variance. Results challenge traditional intelligence nosologies and suggest consideration of a two-step method of WAIS-IV interpretation in clinical samples, whereby the Full Scale IQ score (FSIQ) score is examined first and individual subtest scores are analyzed second.

Head Growth and Intelligence from Birth to Adulthood in Very Preterm and Term Born Individuals

OBJECTIVES

The aim of this study was to investigate the effects of infant and toddler head growth on intelligence scores from early childhood to adulthood in very preterm (&lt;32 weeks gestational age; VP) and/or very low birth weight (&lt;1500 g; VLBW) and term born individuals.

METHODS

203 VP/VLBW and 198 term comparisons were studied from birth to adulthood as part of the prospective geographically defined Bavarian Longitudinal Study (BLS). Head circumference was assessed at birth; 5, 20 months; and 4 years of age. Intelligence was assessed with standardized tests in childhood (6 and 8 years: K-ABC) and at 26 years (Wechsler Adult Intelligence Scale, WAIS). Structural equation modeling (SEM) was used to model the effect of head growth on IQ.

RESULTS

On average, VP/VLBW had lower head circumference at birth (27.61 cm vs. 35.11 cm, mean difference 7.49, 95% confidence interval [7.09-7.90]) and lower adult intelligence scores (88.98 vs. 102.54, mean difference 13.56 [10.59-16.53]) than term born comparison individuals. Head circumference at birth (e.g., total effect β=.48; p&lt;.001 for adult IQ) and head growth in childhood predicted intelligence development from age 6 to 26 years in both VP/VLBW and term born individuals (70% of variance in adult IQ explained by full model). Effects of gestation and birth weight on intelligence were fully mediated by head circumference and growth.

CONCLUSIONS

This longitudinal investigation from birth to adulthood indicates head growth as a proxy of brain development and intelligence. Repeated early head circumference assessment adds valuable information when screening for long-term neurocognitive risk. (JINS, 2019, 25, 48#x2013;56).

Verbal intelligence in bilinguals when measured in L1 and L2

This study was aimed at studying the Verbal IQ in two groups of Spanish/English bilinguals: simultaneous and early sequential bilinguals. 48 Spanish/English bilinguals born in the U.S. or Latin American countries but moving to United States before the age of 10 were selected. The verbal subtests of the Wechsler Adult Intelligence Scale (English and Spanish) - Third Edition (WAIS-III) was administered. Overall, performance was significantly better in English for both groups of bilinguals. Verbal IQ difference when tested in Spanish and English was about one standard deviation higher in English for simultaneous bilinguals, and about half standard deviation for early sequential bilinguals. In both groups, Verbal IQ in English was about 100; considering the level of education of our sample (bachelor degree, on average), it can be assumed that Verbal IQ in English was lower than expected, suggesting that bilinguals may be penalized even when evaluated in the dominant language.

A Brief Assessment of Intelligence Decline in Schizophrenia As Represented by the Difference between Current and Premorbid Intellectual Quotient

Patients with schizophrenia elicit several clinical features, such as psychotic symptoms, cognitive impairment, and subtle decline of intelligence. The latter two features become evident around the onset of the illness, although they may exist even before the disease onset in a substantial proportion of cases. Here, we review the literature concerning intelligence decline (ID) during the progression of schizophrenia. ID can be estimated by comparing premorbid and current intellectual quotient (IQ) by means of the Adult Reading Test and Wechsler Adult Intelligence Scale (WAIS), respectively. For the purpose of brief assessment, we have recently developed the WAIS-Short Form, which consists of Similarities and Symbol Search and well reflects functional outcomes. According to the degree of ID, patients were classified into three distinct subgroups; deteriorated, preserved, and compromised groups. Patients who show deteriorated IQ (deteriorated group) elicit ID from a premorbid level (≥10-point difference between current and premorbid IQ), while patients who show preserved or compromised IQ do not show such decline (<10-point difference). Furthermore, the latter patients were divided into patients with preserved and compromised IQ based on an estimated premorbid IQ score >90 or below 90, respectively. We have recently shown the distribution of ID in a large cohort of schizophrenia patients. Consistent with previous studies, approximately 30% of schizophrenia patients had a decline of less than 10 points, i.e., normal intellectual performance. In contrast, approximately 70% of patients showed deterioration of IQ. These results indicate that there is a subgroup of schizophrenia patients who have mild or minimal intellectual deficits, following the onset of the disorder. Therefore, a careful assessment of ID is important in identifying appropriate interventions, including medications, cognitive remediation, and social/community services.

WAIS-IV Seven-Subtest Short Form: Validity and Clinical Use in Schizophrenia

OBJECTIVE

This study assesses the psychometric properties of Ward's seven-subtest short form (SF) for WAIS-IV in a sample of adults with schizophrenia (SZ) and schizoaffective disorder.

METHOD

Seventy patients diagnosed with schizophrenia or schizoaffective disorder were administered the full version of the WAIS-IV. Four different versions of the Ward's SF were then calculated. The subtests used were: Similarities, Digit Span, Arithmetic, Information, Coding, Picture Completion, and Block Design (BD version) or Matrix Reasoning (MR version). Prorated and regression-based formulae were assessed for each version.

RESULTS

The actual and estimated factorial indexes reflected the typical pattern observed in schizophrenia. The four SFs correlated significantly with their full-version counterparts, but the Perceptual Reasoning Index (PRI) correlated below the acceptance threshold for all four versions. The regression-derived estimates showed larger differences compared to the full form. The four forms revealed comparable but generally low clinical category agreement rates for factor indexes. All SFs showed an acceptable reliability, but they were not correlated with clinical outcomes.

CONCLUSIONS

The WAIS-IV SF offers a good estimate of WAIS-IV intelligence quotient, which is consistent with previous results. Although the overall scores are comparable between the four versions, the prorated forms provided a better estimation of almost all indexes. MR can be used as an alternative for BD without substantially changing the psychometric properties of the SF. However, we recommend a cautious use of these abbreviated forms when it is necessary to estimate the factor index scores, especially PRI, and Processing Speed Index.

The Longitudinal Impact of Hearing Impairment on Cognition Differs According to Cognitive Domain

Identification and modification of the risk factors for cognitive decline throughout the adult life span are priority subjects in a progressively aging society; however, much remains to be learned. The aim of this study was to understand whether changes in cognitive function can be affected by hearing impairment (HI) and whether the impact of HI differs depending on the cognitive domain. A total of 1109 individuals aged 60-79 years at baseline who participated in the Longitudinal Study of Aging at the National Institute for Longevity Sciences (NILS-LSA) was followed up for a maximum of 13.3 years. Cognitive function was evaluated using four subtests of the Japanese Wechsler Adult Intelligence Scale-Revised Short Forms (JWAIS-R-SF): namely, Information, Similarities, Picture Completion, and the Digit Symbol Substitution subtests. The HI was defined as a pure-tone average of the better ear >25 dB. A longitudinal analysis of 4437 observations obtained during a follow-up period of approximately 12 years was performed. We estimated linear changes in subtest scores by HI status, using the time-varying mixed-effects regression model, which included fixed terms for the intercept, HI status at baseline, time (years elapsed since baseline) and an HI × time interaction term adjusted for age at baseline, sex, education, and other possible confounders. There were significant main effects of HI on the scores of the four subtests after adjustment. The HI × time interaction was significant for the scores of the Information (p = 0.001) and Digit Symbol Substitution subtests (p = 0.001). The scores of the HI group declined faster in the Information and Digit Symbol Substitution subtests compared to those in the no-HI group. The model-predicted 12-year slope using a mean baseline age (68.7 years) indicated no significant decline in the individuals without HI at baseline for the Information and Similarities subtests, however, this tolerance was lost in the individuals with HI. In conclusion, the present observation showed that the impact of HI on cognition was longitudinally significant and implied that the effect differs according to cognitive domain.

Self-appraisal: Estimates of intellectual performance for persons with Acquired Brain Injury

BACKGROUND

Acquired Brain Injury (ABI) limits a survivor's ability to appraise their task performance. There are, however, few measures of self-appraisal.

OBJECTIVE

This study developed a technique for measuring self-appraisal originally proposed by Wilbur, Wilk, Silver, and Parente (2008).

METHODS

A multivariate model of self-appraisal that includes measures of predicted performance as well as measures of over- and under-estimation of performance was evaluated with ABI survivors, participants with diagnosed learning disabilities, and others with emotional impairments to determine which measures were the most sensitive to the differences among the groups.

RESULTS

This model provided a more accurate assessment of self-appraisal than the one previously proposed by Wilbur et al. (2008). The two measures of self-appraisal measure different psychological processes, and the overall model measures aspects of performance that are unrelated to an individual's IQ. A measure of over- or under-estimation of performance was the most sensitive component of the model.

CONCLUSIONS

Self-appraisal is a multi-dimensional concept, with at least two main components. The findings corroborate previous literature suggesting that persons with ABI have difficulty accurately assessing their task performance resulting in inflated performance judgments. This self-appraisal technique can be applied to most assessments of performance.

Effect of thyroid hormone replacement therapy on cognition in long-term survivors of aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a recently identified risk factor for chronic hypothyroidism. Patients with hypothyroidism often exhibit cognitive dysfunction. The aim of the present study was to determine the effects of thyroid hormone replacement therapy on cognition in aSAH survivors with hypothyroidism. A study population of 135 patients was recruited and subjected to the Montreal Cognitive Assessment (MoCA) and Beck Depression Inventory. Among the study population, 52 patients exhibited cognitive dysfunction. Thyroid hormone levels were measured in these patients using an electrochemiluminescence immunoassay in order to elucidate possible deficits in the thyrotrophic hormonal axes, and hypothyroidism was confirmed in 31 patients. Among these 31 patients, 22 patients consented to be randomized into groups and were administered levothyroxine replacement or a placebo treatment for 3 months. The MoCA and Wechsler Adult Intelligence Scale-Chinese version (WAIS-RC) testing were performed prior to and following the replacement therapy or placebo treatments. All subjects completed the study with no negative side effects. After 8-12 weeks of oral levothyroxine administration, it was observed that the serum concentration of thyroid-stimulating hormone was restored to normal levels. Furthermore, neuropsychological test results improved following the replacement therapy. A significant improvement was observed in the MoCA scores of the replacement group following therapy, with the exception of the score for abstraction. Additionally, significant improvements in the WAIS-RC were observed in the replacement group, with the exceptions of the information comprehension and letter-number sequencing scores. Thus, the present study has demonstrated the partial normalization of cognitive impairments in patients with hypothyroidism following aSAH as a result of appropriate levothyroxine replacement therapy.

Brainstem auditory evoked potentials with the use of acoustic clicks and complex verbal sounds in young adults with learning disabilities

PURPOSE AND BACKGROUND

Acoustic signals are transmitted through the external and middle ear mechanically to the cochlea where they are transduced into electrical impulse for further transmission via the auditory nerve. The auditory nerve encodes the acoustic sounds that are conveyed to the auditory brainstem. Multiple brainstem nuclei, the cochlea, the midbrain, the thalamus, and the cortex constitute the central auditory system. In clinical practice, auditory brainstem responses (ABRs) to simple stimuli such as click or tones are widely used. Recently, complex stimuli or complex auditory brain responses (cABRs), such as monosyllabic speech stimuli and music, are being used as a tool to study the brainstem processing of speech sounds. We have used the classic 'click' as well as, for the first time, the artificial successive complex stimuli 'ba', which constitutes the Greek word 'baba' corresponding to the English 'daddy'.

PATIENTS AND METHODS

Twenty young adults institutionally diagnosed as dyslexic (10 subjects) or light dyslexic (10 subjects) comprised the diseased group. Twenty sex-, age-, education-, hearing sensitivity-, and IQ-matched normal subjects comprised the control group. Measurements included the absolute latencies of waves I through V, the interpeak latencies elicited by the classical acoustic click, the negative peak latencies of A and C waves, as well as the interpeak latencies of A-C elicited by the verbal stimulus 'baba' created on a digital speech synthesizer.

RESULTS

The absolute peak latencies of waves I, III, and V in response to monoaural rarefaction clicks as well as the interpeak latencies I-III, III-V, and I-V in the dyslexic subjects, although increased in comparison with normal subjects, did not reach the level of a significant difference (p<0.05). However, the absolute peak latencies of the negative wave C and the interpeak latencies of A-C elicited by verbal stimuli were found to be increased in the dyslexic group in comparison with the control group (p=0.0004 and p=0.045, respectively). In the subgroup consisting of 10 patients suffering from 'other learning disabilities' and who were characterized as with 'light' dyslexia according to dyslexia tests, no significant delays were found in peak latencies A and C and interpeak latencies A-C in comparison with the control group.

CONCLUSIONS

Acoustic representation of a speech sound and, in particular, the disyllabic word 'baba' was found to be abnormal, as low as the auditory brainstem. Because ABRs mature in early life, this can help to identify subjects with acoustically based learning problems and apply early intervention, rehabilitation, and treatment. Further studies and more experience with more patients and pathological conditions such as plasticity of the auditory system, cochlear implants, hearing aids, presbycusis, or acoustic neuropathy are necessary until this type of testing is ready for clinical application.

Cognitive outcome in adolescents and young adults after repeat courses of antenatal corticosteroids

OBJECTIVE

To investigate whether repeat courses of antenatal corticosteroids have long-term effects on cognitive and psychological functioning.

STUDY DESIGN

In a prospective cohort study, 58 adolescents and young adults (36 males) who had been exposed to 2-9 weekly courses of betamethasone in utero were assessed with neuropsychological tests and behavior self-reports. Unexposed subjects (n = 44, 25 males) matched for age, sex, and gestational age at birth served as a comparison group. In addition, individuals exposed in utero to a single course (n = 25, 14 males) were included for dose-response analysis. Group differences were investigated using multilevel linear modeling.

RESULTS

Mean scores obtained in 2 measures of attention and speed were significantly lower in subjects exposed to 2 or more antenatal corticosteroids courses (Symbol Search, P = .009; Digit Span Forward, P = .02), but these were not dose-dependent. Exposure to repeat courses of antenatal corticosteroids was not associated with general deficits in higher cognitive functions, self-reported attention, adaptability, or overall psychological function.

CONCLUSIONS

Although this study indicates that repeat exposure to antenatal corticosteroids may have an impact on aspects of executive functioning, it does not provide support for the prevailing concern that such fetal exposure will have a major adverse impact on cognitive functions and psychological health later in life.

Neurocognitive functioning in adults with phenylketonuria: results of a long term study

OBJECTIVES

A controlled long-term study was performed to assess the neurological and neuropsychological performance in adult patients with early-treated phenylketonuria (PKU).

METHODS

We investigated 57 patients with early-treated classical PKU aged 19 to 41 years (mean age 31 years) and 46 matched healthy controls, matched for age and socioeconomic status. Patients and controls were assessed for their intelligence quotient (IQ), and attention and information-processing abilities. Magnetic resonance imaging (MRI) of the brain was performed in all patients. Neuropsychological assessments and MRI were repeated at a five-year-follow-up.

RESULTS

In the five-year interval IQ, information processing and attention of patients and controls remained constant. At both assessment times the IQ scores were significantly lower in patients compared to controls. Older adult patients (>32 years) showed poorer information processing and attention at both assessment times compared to young adult patients (<32 years) and controls. IQ, information processing and attention showed no correlation to imaging results but were significantly correlated to blood phenylalanine (Phe) levels in patients' childhood and adolescence, and Phe levels had been higher in the adolescent years of older adult patients.

CONCLUSIONS

Cognitive performance in adult patients with early-treated PKU does not seem to be subject to deterioration observable in a five-year interval. Neuropsychological assessment in adults with PKU revealed neurocognitive impairment particularly in older adult patients. This seems to refer to an early relaxation of diet that was recommended when the older patients were adolescents. Results indicate a benefit of dietary control during adolescence in PKU.