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.     

Pavlovian conditioning: the CS-UR relation

A new Pavlovian procedure used fluid-elicited throat-movement responses of the pigeon (N=66) to study the effects on conditioning of the temporal relation of the conditioned stimulus (CS) to the unconditioned stimulus-unconditioned response (US-UR). Because the throat-movement response has a substantial latency and duration, the relation of the CS to the US and UR could be independently evaluated. Four experiments indicated that, operationally, the relation of the CS to the UR--not to the US--is critical for conditioning in this preparation. The conventional emphasis on CS-US relations is based on procedures that confound the occurrence of the US with the UR and that foster generalization decrement between training and testing. The authors indicate how several conditioning phenomena may be reinterpreted in terms of CS-UR relations.     

Using the multifaceted Rasch model to improve the TAT/PSE measure of need for achievement

We used the Rasch (1980) model to develop new pictures for the Thematic Apperception Test (C. D. Morgan & Murray, 1938; McClelland, Atkinson, Clark, & Lowell, 1953) or picture story exercise to measure need for achievement (nAch). In Experiments 1 and 2, we analyzed stories to assess the difficulty level of a total of 8 pictures using the multifaceted Rasch model with picture difficulty, story probe difficulty, and participant ability as facets with a partial credit model (FACETS; Linacre, 2005). A total of 6 pictures were retained and 4 new ones added for Experiment 3 in which 201 participants wrote 6 stories to a random set of the 10 pictures. FACETS analysis revealed improved person separation reliability. In Experiment 4, 206 participants wrote 1 story to the Studying picture either before or after filling out a battery of achievement-related questionnaires. The 2 experimental groups did not differ in the amount of nAch in their stories. The coder facet was demonstrated with 2 independent coders using the revised coding system for nAch.     

Individual differences in anxiety trait are related to spatial learning abilities and hippocampal expression of mineralocorticoid receptors

Although high levels of anxiety might be expected to negatively influence learning and memory, it remains to be shown whether individual differences in anxiety may influence spatial learning and memory in outbred rat populations. We have studied this possibility in male Wistar rats whose levels of anxiety were first characterized as either high (HA) or low (LA) according to their behavior in the elevated plus maze or in the open field test. Subsequently, their performance in the Morris water maze was studied, a task dependent on hippocampal activity. Interestingly, LA rats showed a faster acquisition and better memory in the water maze when compared to HA rats. Indeed, this difference in performance could mainly be attributed to the increase in thigmotactic behavior (swimming in circles close to the maze walls) displayed by HA rats during spatial navigation. Glucocorticoids are known to affect the state of anxiety and the hippocampus is the main target of glucocorticoids in the brain. Hence, we investigated whether the hippocampal expression of the two classical corticosteroid receptors, mineralocorticoid (MR) and glucocorticoid (GR) differed in the two groups of rats. We found that LA rats displayed higher hippocampal expression of MR but not GR than HA rats. Indeed, the expression levels for these receptors were positively correlated with the amount of time spent by the animals in the open arms of the elevated plus maze. Moreover, we present evidence that the levels of anxiety quantified in the first stages of our study constitute a trait rather than a state. Taken together, this study has generated evidence of a close interaction between the anxiety trait, hippocampal MR expression and the learning abilities of individuals in stressful spatial orientation tasks.     

Victim and offender accounts of interpersonal conflict: autobiographical narratives of forgiveness and unforgiveness

Participants wrote 2 narratives that described an incident in which they angered or hurt someone (offender) or in which someone angered or hurt them (victim) and the offense was forgiven or not forgiven. Victims portrayed the offense as continuing (open), and offenders portrayed the offense as over (closed). Forgiveness narratives portrayed offenses as closed and with positive outcomes; however, for some victims, forgiveness coincided with continued anger, suggesting incomplete forgiveness. Dispositional empathy was associated with more benign interpretations of offenses, and situational empathy (e.g., for the offender) was associated with victims' forgiveness. In contrast, offenders' empathy for victims was associated with less self-forgiveness. Thus, both victim or offender role and forgiveness must be considered to understand narratives of interpersonal offenses.     

Psychology of learning: a new approach to study behavior of Rhodnius prolixus stal under laboratory conditions

Conditioning methodologies associated with the psychology of learning are suggested as a new strategy to investigate behavior of the assassin bug Rhodnius prolixus, which is the main vector of Chagas disease in Venezuela. Chagas disease is the fourth leading cause of death in Latin America, as it causes severe chronic illness and approximately 43,000 deaths per year. To illustrate this strategy, two preliminary experiments are reported. In the first, Pavlovian conditioning was examined by pairing an olfactory conditioned stimulus with a temperature unconditioned stimulus. A temperature of 42 degrees C elicits a complex behavioral sequence in R. prolixus consisting of proboscis extension and crawling. Over the course of 12 training trials, this behavioral sequence was not elicited by an olfactory conditioned stimulus. In the second experiment, a latent inhibition paradigm was used to pre-expose R. prolixus to an olfactory conditioned stimulus before pairing the odor with temperature. Over the course of training, an effect of pre-exposure was found. Suggestions for research are discussed and potential conditioned and unconditioned stimuli identified.     

Perceived frequency of domestic violence against women and neighbourhood social disorder

Regression analyses from a nationally representative sample of 10,235 adult Spaniards, provided in 1995 from the Spanish Demands of Security and Victimization Survey, showed a small and positive relationship between high neighbourhood social disorder and perceived frequency of domestic violence against women in Spanish families, after controlling for sociodemographic variables and size of city. Among sociodemographic variables, sex had the strongest association with neighbourhood social disorder, being more than twice as large as neighbourhood social disorder.     

Facial appearance and judgments of credibility: the effects of facial babyishness and age on statement credibility

Researchers have found that facial appearance influences social judgments. For example, evidence has shown that facial babyishness and age affect perceivers' impressions of the stimulus person's veracity. In this experiment, the researchers examined whether these variables also influenced the credibility attributed to written statements purportedly made by these people in addition to several topics of interest in deception-detection research. Undergraduates (N = 270) were presented babyfaced or mature-faced photographs that depicted a child, an adult, or an older individual, in addition to a written truthful or deceptive statement purportedly made by the person in the photograph. Results showed that, as predicted, when the statements were accompanied by babyfaced pictures, participants tended to judge them as truthful, but only if the pictures did not depict children. Also, when the statements were accompanied by childen's pictures, participants tended to judge them as deceptive, but only if the pictures depicted a babyish face. Overall detection accuracy was close to chance and did not correlate with either judgmental confidence or with the respondents' estimated lie-detection accuracy. However, confidence and estimated ability were significantly correlated. Also, more confidence was placed in judgments of truthfulness than in judgments of deceptiveness. Respondents' truth bias and the existence of a veracity effect in the diverse experimental conditions were examined as well.     

An example of rehabilitation of speech by mediation-techniques in aphasia

In a case of severe aphasia it was attempted to use a mediation technique. During several months there was no improvement in speech by using the usual techniques. The patient had to learn several gestures that corresponded to different letters. This technique result in a considerable speech improvement. It is discussed which mechanisms are possibly involved in the rehabilitation process; the practical importance of the mediation technique is suggested.