Serum β-Amyloid Correlates with Neuropsychological Impairment

ABSTRACT

Aims: Evidence suggests a relationship between peripheral Aβ and AD. We hypothesized that higher levels of serum Aβ_1–42 would be associated with memory impairment, thought to occur early in the disease, and rises in serum Aβ_1–40, which occur later, would be associated with impairment in non-memory measures. Methods: Using a cross-sectional design, we examined the relationship of serum Aβ_1–40, Aβ_1–42, and the ratio of Aβ_{1–42/1–40} to neuropsychological measures in 40 cognitively normal controls, 13 MCI subjects, and 25 AD patients. Results: Serum Aβ_1–42 and the ratio of Aβ_{1–42/1–40} were significantly higher in the MCI group compared to the controls. A significant relationship in the hypothesized direction (poorer scores associated with higher Aβ_1–40 serum levels) was found between Aβ_1–40 and measures of executive functions across the entire cohort of individuals tested and with measures of language and processing speed in the AD group. Regression analysis found that neuropsychological measures accounted for 26% of the variance in serum Aβ_1–40, in the MCI/AD but not the controls. Furthermore that language and executive measures were significant predictors. Conclusions: Results provide preliminary data to partially support our hypotheses and suggest that changes in serum Aβ levels may be attributed to pathological changes within the brain.     

Social-Cognitive Functioning and Schizotypal Characteristics

The authors examined the relationship between social cognition and a feature of schizotypal personality referred to as magical ideation, defined broadly as the presence and intensity of illogical beliefs about causality and the nature of reality. The measures of social cognition used in this study were the Character Intention Task (CIT) and the adult version of the Reading the Mind in the Eyes Test. Regression analyses indicated that understanding of character intentions, as measured by CIT scores, and ability to identify emotions on the Eyes test were related to non-realistic beliefs. Principal components analysis of the Magical Ideation Scale generated 3 factors: Occult Beliefs, Non-Realism, and New Age Ideas. Results indicated that impaired understanding of character intentions and ability to identify emotions on the Eyes test were related to non-realistic beliefs. Understanding the cognitive impairments associated with schizotypal characteristics can facilitate development of more targeted therapeutic interventions.     

Investigating medical decision‐making capacity in patients with cognitive impairment using a protocol based on linguistic features

A critical question is whether cognitively impaired patients have the competence for autonomous decisions regarding participation in clinical trials. The present study aimed to investigate medical decision‐making capacity by use of a Swedish linguistic instrument for medical decision‐making (LIMD) in hypothetical clinical trials in patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI). Three comparable groups (age, education) participated in the study: AD (n = 20; MMSE: 24.1 ± 3.3) and MCI (n = 22; MMSE: 26.7 ± 2.4) patients and healthy controls (n = 37; MMSE: 29.1 ± 1.0). Medical decision‐making capacity was operationalized as answers to questions regarding participation in three hypothetical clinical trials. Answers were scored regarding comprehension, evaluation and intelligibility of decisions, and a total LIMD score was used as the measure of medical decision‐making ability. Groups differed significantly in LIMD with AD patients performing worst and MCI poorer than the control group. A strong association was found between all LIMD scores and diagnosis which supported the assertion that LIMD as it is designed is a one‐dimensional instrument of medical decision‐making capacity (MDMC). The results indicate that a fundamental communicative ability has an impact on the competence for autonomous decisions in cognitive impairment.     

Diagnosis of cognitive impairment onset in older adults based on limitations in language skills / Diagnóstico del inicio del deterioro cognitivo en mayores a partir de limitaciones en las capacidades lingüísticas

Abstract

Progressive decline in language has been described in neuropsychological studies on Alzheimer’s disease and Mild Cognitive Impairment (MCI). We investigate this decline in its early stages, as well as its manifestations and the linguistic differences between participants at risk of developing MCI and without impairment. Participants were 36 older adults, all aged over 65. They were assessed using 31 subtests grouped into eight areas: fluency, comprehension, oral expression, reading, writing, memory, perceptual organization and processing speed. Our results showed significant differences between participants at risk of developing MCI and without impairment in verbal tests but not in manipulative tests. All participants at risk of developing MCI scored lowest in these eight areas. Our findings illustrate the relevance of investigating language skills in people at risk of developing MCI. Investigating these neuropsychological changes will help design appropriate intervention programmes that affect areas with higher levels of impairment.     

Positive emotion can protect against source memory impairment

Despite widespread belief that memory is enhanced by emotion, evidence also suggests that emotion can impair memory. Here we test predictions inspired by object-based binding theory, which states that memory enhancement or impairment depends on the nature of the information to be retrieved. We investigated emotional memory in the context of source retrieval, using images of scenes that were negative, neutral or positive in valence. At study each scene was paired with a colour and during retrieval participants reported the source colour for recognised scenes. Critically, we isolated effects of valence by equating stimulus arousal across conditions. In Experiment 1 colour borders surrounded scenes at study: memory impairment was found for both negative and positive scenes. Experiment 2 used colours superimposed over scenes at study: valence affected source retrieval, with memory impairment for negative scenes only. These findings challenge current theories of emotional memory by showing that emotion can impair memory for both intrinsic and extrinsic source information, even when arousal is equated between emotional and neutral stimuli, and by dissociating the effects of positive and negative emotion on episodic memory retrieval.     

Robust anger: Recognition of deteriorated dynamic bodily emotion expressions

In two studies, the robustness of anger recognition of bodily expressions is tested. In the first study, video recordings of an actor expressing four distinct emotions (anger, despair, fear, and joy) were structurally manipulated as to image impairment and body segmentation. The results show that anger recognition is more robust than other emotions to image impairment and to body segmentation. Moreover, the study showed that arms expressing anger were more robustly recognised than arms expressing other emotions. Study 2 added face blurring as a variable to the bodily expressions and showed that it decreased accurate emotion recognition—but more for recognition of joy and despair than for anger and fear. In sum, the paper indicates the robustness of anger recognition in multileveled deteriorated bodily expressions.     

Early Language Impairment and Young Adult Delinquent and Aggressive Behavior

Clinic and forensic studies have reported high rates of language impairments in conduct disordered and incarcerated youth. In community samples followed to early adolescence, speech and language impairments have been linked to attention deficits and internalizing problems, rather than conduct problems, delinquency, or aggression. This study examines the young adult antisocial outcomes of speech or language impaired children. Language impaired boys had higher levels of parent-rated delinquency symptoms by age 19 than boys without language impairment, controlled for verbal IQ and for demographic and family variables. Language impaired boys did not differ from controls in self-reported delinquency or aggression symptoms on a standardized checklist; however, language impaired boys reported higher rates of arrests and convictions than controls. Language impairment was not related to aggression or delinquency in girls. We examine alternate models of the interrelationships between language, academics, and behavior, at ages 5, 12, and 19.     

The Association Between Delirium and Cognitive Decline: A Review of the Empirical Literature

Delirium is a common neurobehavioral syndrome that occurs across health care settings which is associated with adverse outcomes, including death. There are limited data on long-term cognitive outcomes following delirium. This report reviews the literature regarding relationships between delirium and cognitive impairment. Psych Info and Medline searches and investigation of secondary references for all English language articles on delirium and subsequent cognitive impairment were carried out. Nine papers met inclusion criteria and documented cognitive impairment in patients following delirium. Four papers reported greater cognitive impairment among patients with delirium than matched controls. Four papers reported higher incidence of dementia in patients with a history of delirium. One study found 1 of 3 survivors of critical illness with delirium developed cognitive impairment. The evidence suggests a relationship between delirium and cognitive impairment, although significant questions remain regarding the nature of this association. Additional research on delirium-related effects on long-term cognitive outcome is needed.     

Neuropsychological function in a group of patients 25 years after sustaining minor head injuries as children and adolescents

Previous studies suggest that neuropsychological impairment following mild to moderate pediatric head injury may become persistent and interrupt the normal course of intellectual development. In this study 45 subjects were assessed with a standardized neuropsychological test battery 25 years after sustaining mild to moderate head injury as children. Although the group scores in the normal range, significant relations between head injury severity and current neuropsychological function were found. The most important predictor of poor outcome was length of PTA at injury, EEG pathology, and loss of consciousness at injury. No significant influence of pre- and post-injury risk factors on current neuropsychological function was evident. The findings support the view that complicated mild and moderate paediatric head injury may heighten the risk of developing subtle neuropsychological problems later in life.