The contributions of memory and attention processes to cognitive abilities

In two experiments, the contributions of memory and attention processes to the cognitive abilities of reasoning and perceptual speed were investigated. Two measures of speed of information retrieval from long-term and short-term memory (Posner paradigm, Sternberg paradigm) and two attention measures (continuous attention test, attention switching test) were included in the first experiment (N = 220). The memory tests led to correlations with the measures of cognitive abilities, whereas the attention test did not. The same tests as well as one additional memory test and one attention test (working memory test, test of covert orientation) were administered in the second experiment (N = 116). Again, the memory tests led to the larger correlations with the measures of cognitive abilities. Two components were obtained in components analysis, of which the first was characterized by high loadings of the memory tests and the second by high loadings of the attention tests. Only the memory component contributed to the prediction of cognitive abilities.     

Out of sight,out of mind? Relations between visual acuity and cognition

Prior research has established significant relations between measures of sensory ability and cognitive function in adults of different ages, and several explanations for this relation have been proposed. One explanation is that sensory abilities restrict cognitive processing, a second is that cognitive abilities influence assessments of sensory ability, and a third is that both sensory function and cognition are affected by a common, potentially age-based, third factor. These explanations were investigated using mediation and moderation analyses, with near visual acuity as the sensory measure and scores on visual speed tests and auditory memory tests as the cognitive measures. Measures of visual acuity, speed, and memory were obtained from three moderately large samples, two cross-sectional (N?=?380, N?=?4,779) and one longitudinal (N?=?2,258), with participants ranging from 18 to 90 years of age. The visual acuity and cognitive measures had different age trajectories, and the visual acuity–cognition relations were similar in each 5-year age band. The results suggest that the age-related differences and changes in near visual acuity are unlikely to contribute to the age-related differences and changes in speed and memory measures.     

The relationship between speed of information processing and cognitive ability

Speed of information processing as measured by various reaction time and inspection tasks has been shown to correlate with psychometric intelligence, and it has been suggested that general intelligence (g) is determined to some degree by the speed that information is processed. If this is so, then various measures of speed of information processing should correlate substantially with each other, and each should also correlate with a wide range of psychometric tests that load on g. Alternatively, intelligence may be considered to be a multi-faceted complex of partially related abilities with specific abilities being dependent upon specific cognitive processes. If this is the case, it should be possible to discover independent cognitive processes, some of which correlate with one facet or broad ability and some with another. This paper presents three experiments in which the relationship between intellectual ability and four speed of information processing measures was examined. These were rate of memory scanning, rate of retrieval of information from long term memory, speed of stimulus-response mapping and inspection time (IT). Results showed that correlations between IT and most reaction time measures of speed of information processing were low, and that correlations between different versions of IT were negligible. In addition, some cognitive tasks with verbal material (memory scanning rate for digits and Posner letter matching IT) correlated most substantially with Verbal Reasoning whereas non-verbal (two-line) IT consistently correlated with tests loading on g. It was thus suggested that while non-verbal IT may be a measure of a perceptual speed attribute that contributes to mental functioning, other “speed of information processing” parameters may be more specific to a subset of abilities.     

Long-term concentrative meditation and cognitive performance among older adults

ABSTRACT

Background: The general consensus that cognitive abilities decline with advancing age is supported by several studies that have reported that older adults perform more poorly on multiple tests of cognitive performance as compared to younger adults. To date, preventive measures against this cognitive decline have been mainly focused on dietary, physical, and lifestyle behaviors which could allow older adults to maintain their cognitive abilities into late life. However, much less stress has been laid on evaluating meditation as a preventive measure in such cases in spite of the fact that the role of meditation on attention has been proved in several studies. In the current study, we extend this preliminary idea, examining the practice of concentrative meditation and the differences in the cognitive performance of older adults who have or have not employed this practice long term. Methodology: This was a cross-sectional study comparing the cognitive performance of meditators and non-meditators in the geriatric age group. Twenty (age > 55 years) long-term practitioners of Vihangam Yoga meditation (>10 years of practice) were recruited in the present study and were applied six paper–pencil neuropsychological tests for assessment of short-term memory, perceptual speed, attention, and executive functioning. The tests used were: (1) the Digit Span test, (2) the Stroop Color Word test, (3) the Trailmaking test, (4) the Letter Cancellation Task, (5) the digit symbol substitution test, and (6) the Rule Shift Card Test. All the tests were also applied to 20 age- and education-matched geriatric adults who have not practiced the meditation technique. Results: Vihangam Yogis showed significantly better performances in all these tests of attention (p < .05) except for the digit backward test, where a trend (p = .08) was found in favor of meditators. Conclusion: Long-term Vihangam Yoga meditators have superior cognitive abilities than non-meditators in the old age group. This technique should be studied further for its ability to prevent age-related cognitive decline.     

Individual differences in false memory from misinformation: Cognitive factors

This research investigated the cognitive correlates of false memories that are induced by the misinformation paradigm. A large sample of Chinese college students (N=436) participated in a misinformation procedure and also took a battery of cognitive tests. Results revealed sizable and systematic individual differences in false memory arising from exposure to misinformation. False memories were significantly and negatively correlated with measures of intelligence (measured with Raven's Advanced Progressive Matrices and Wechsler Adult Intelligence Scale), perception (Motor-Free Visual Perception Test, Change Blindness, and Tone Discrimination), memory (Wechsler Memory Scales and 2-back Working Memory tasks), and face judgement (Face Recognition and Facial Expression Recognition). These findings suggest that people with relatively low intelligence and poor perceptual abilities might be more susceptible to the misinformation effect.     

What cognitive abilities are involved in trail-making performance?

The cognitive abilities involved in the Connections (Salthouse, et al., 2000) version of the trail making test were investigated by administering the test, along with a battery of cognitive tests and tests of complex span and updating conceptualizations of working memory, to a sample of over 3600 adults. The results indicate that this variant of the trail making test largely reflects individual differences in speed and fluid cognitive abilities, with the relative contributions of the two abilities varying according to particular measure of performance considered (e.g., difference, ratio, or residual). Relations of age on trail making performance were also examined. Although strong age differences were evident in the Connections and working memory measures, with both sets of variables there was nearly complete overlap of the age differences with individual differences in speed and fluid cognitive abilities.     

Convergence between attention variables and factors of psychometric intelligence in older adults

The purpose of the present study was to examine the hypothesis that individual differences on measures of attention would converge with select factors of psychometric intelligence, especially fluid intelligence and short-term acquisition and retrieval. A sample of 83 elderly adults $\text{(}\text{X}\text{= 71}\text{years}\text{)}$ was administered a battery of 17 psychometric ability tests. Tests were selected to mark four psychometric ability factors (Cattell and Horn's dimensions of fluid and crystallized intelligence, short-term acquisition and retrieval, and perceptual speed). Also, seven tasks representing four aspects of attention—decoding processes, selective attention, attention switching, and concentration—were administered. A confirmatory factor analysis was conducted to examine the relationships among the four psychometric ability factors and 11 variables obtained from the attention tasks. Results were only partially consistent with the hypothesized pattern of convergence. Two attention measures had significant loadings on a fluid-type intelligence factor, and one had a marginally significant loading on a short-term memory factor. In general, the greatest convergence occured between attention variables and the ability factor of Perceptual Speed. Results were discussed with respect to previous research on psychometric abilities and cognitive processes, the theory of fluid-crystallized intelligence, and their implications for understanding intellectual aging.     

加工速度和工作记忆在认知年老化过程中的作用

研究加工速度和工作记忆在认知能力年老化过程中的作用。被试为20-90岁的健康成人1350名,完成加工速度、工作记忆及一组认知能力测验,应用分层回归分析方法考查在年老化过程中加工速度和工作记忆对多项认知变量的作用量。结果表明,在年老化过程中,加工速度和工作记忆对认知变量的作用量分别约为87% 和76%;二者的综合作用量约为94%。说明加工速度和工作记忆在认知能力年老化过程中起决定作用     

Impaired frontostriatal cognitive functioning following posteroventral pallidotomy in advanced Parkinson's disease

We investigated the long-term effects of posteroventral pallidotomy on tests sensitive to the functional integrity of frontostriatal neural systems in a sample of 11 patients with advanced Parkinson's disease (PD). Patients were assessed within 1 month prior to surgery and at 12 months following pallidotomy. Changes in outcome measures were compared to a control sample of equally performing PD patients receiving nonsurgical medical management assessed over a 12-month period. Measures of cognitive abilities sensitive to frontostriatal functional integrity tested psychomotor processing speed, executive components of working memory, and reasoning. Additional tests of general mental status and semantic memory ability were utilized to assess the specificity of the effect of pallidotomy on cognitive function. Significant declines in performance on all measures sensitive to frontostriatal integrity were found for the surgery group but not the PD control group. No significant changes in performance were found on the measures of general mental status or semantic memory for either the surgery or PD control samples. These results suggest that the posteroventral pallidotomy selectively impairs performance on tests of frontostriatal cognitive abilities.     

Hyperactivity and pediatrician diagnoses,parental ratings,specific cognitive abilities,and laboratory measures

Children diagnosed as hyperactive and treated for hyperactivity by private pediatricians were compared to a large unselected sample of children on parental ratings of behavioral problems (Conners Symptoms Rating Questionnaire), laboratory measures (a week-long assessment of locomotion as measured by pedometers, sustained attention, selective attention, fidgeting, and aggressiveness), and 10 tests of specific cognitive abilities (verbal reasoning, spatial reasoning, memory, and perceptual speed). Test-retest reliability was obtained for all measures. The results indicated that pediatrician diagnoses of hyperactivity are related to parental ratings but not to laboratory assessments. Diagnoses by private pediatricians may include more heterogeneous and nonspecific behavioral problems than diagnoses made in most research contexts. Pediatrician diagnoses were related to deficits in specific cognitive abilities, most notably perceptual speed and verbal ability. Hyperactivity as diagnosed by private pediatricians may reflect deficits in skills necessary to pace oneself appropriately in school-related tasks. In general, these results suggest that the criteria and methods used to diagnose hyperactivity deserve greater attention.We are grateful to the Spencer Foundation for their support of this research. Preparation of this report was supported in part by a Research Scientist Development Award (AA-00041) from the ADAMHA NIAAA.     

Cognitive functioning and neuroticism in an elderly community sample

The relationship between neuroticism and cognitive functioning was investigated using data from a community survey of the elderly. Contrary to Pearson (1993, Personality and Individual Differences, 14, 265–266), neuroticism was related to poorer performance on a number of cognitive measures, but the pattern of correlations differed between men and women. For men there were correlations with a dementia screening test and with tests of episodic memory and fluid intelligence, while for women there were correlations with reaction time measures. It is hypothesized that correlations with neuroticism reflect the effect of chronic stress on cognitive ageing.     

A preliminary investigation of sex differences in associations between emotion regulation difficulties and higher-order cognitive abilities

The present study sought to clarify the cognitive correlates of emotion regulation difficulties (ERD). Further, because prior evidence suggests sex differences in emotion regulation, sex was examined as a moderator of associations between cognitive abilities and ERD. Participants (N = 154) completed self-report measures of ERD, and were administered neuropsychological tests assessing crystallized and fluid intelligence, as well as various components of executive functioning. Bivariate correlations and results from regression analyses suggested sex-dependent associations among cognitive processes and ERD. For men, inhibition of dominant response tendencies was associated with lower ERD, whereas for women, a host of executive abilities (e.g., greater inhibition, cognitive flexibility, semantic processing, abstract reasoning) were associated with greater ERD. Implications for the neurocognitive conceptualization of emotion dysregulation will be discussed.     

Adult age differences in inhibitory processes and their predictive validity for fluid intelligence

According to the inhibition-deficit hypothesis age differences in working memory capacity and fluid intelligence have been attributed to a decline in inhibitory efficiency. Conceptualizing inhibition as multifaceted, 88 participants (49 younger and 39 elderly) completed two versions of the negative priming paradigm (identification and localization), and two variants of the directed forgetting paradigm (listwise and itemwise). Two tasks of the Wechsler Intelligence Test with high loadings on general fluid intelligence (Gf) served as validation criteria. Results revealed task-specific and speed-independent inhibitory deficits in the elderly (lower negative priming in both paradigms; more intrusions in the directed forgetting tasks), as well as higher levels of repetition priming. Significant correlations between measures of inhibition and the Wechsler scores were found in both age groups. Results support the view of multiple inhibitory-like capabilities that play a central role in the decline of higher-order cognitive functions in old age.     

Aging and Working Memory Inside and Outside the Focus of Attention: Dissociations of Availability and Accessibility

ABSTRACT

Two experiments used the N-Back task to test for age differences in working memory inside and outside the focus of attention. Manipulations of the difficulty of item-context binding (Experiment 1) and of stimulus feature binding (Experiment 2) were used to create conditions that varied in their demand on working memory, with the expectation that greater demand might increase age differences in focus-switching costs and the search rate outside the focus of attention. Results showed, however, that although age differences were evident in measures of overall speed and accuracy, and the manipulations significantly affected response times and accuracy in the expected direction, the experimental manipulations had no impact on age differences. Findings instead pointed to age-related reductions in accuracy but not speed of focus-switching and search outside the focus of attention. Thus, age-related deficits appear to involve the availability of representations in working memory, but not their accessibility.     

A family study of memory processes and their relations to cognitive test scores

Members of 118 families (456 individuals) who had been tested on several measures of cognitive ability were retested on the same battery in order to determine test-retest reliability. They then were administered the Wechsler Adult Intelligence Scale and tests of visual memory, auditory memory, and figure memory, as well as other measures not discussed herein. Intercorrelations of memory tasks were low to moderate. Factor analysis resulted in a four factor solution. The different factors appeared to represent auditory sequential memory (Factor I); visual memory, as measured psychometrically (Factor II); visual memory, as measured experimentally (Factor III); and figure memory (Factor IV). A second order factor analysis yielded two factors, one consisting of basically psychometric measures of memory and the other of measures of memory obtained in the experimental psychological tradition. Memory measures generally showed low to moderate positive correlations with scores on the cognitive test battery. Significant spouse correlations were found for 3 of the 11 measures of memory. Significant midparent-midchild regressions were found for 9 of the 11 memory measures.     

Adult Age Differences in Inhibitory Processes and their Predictive Validity for Fluid Intelligence

ABSTRACT

According to the inhibition-deficit hypothesis age differences in working memory capacity and fluid intelligence have been attributed to a decline in inhibitory efficiency. Conceptualizing inhibition as multifaceted, 88 participants (49 younger and 39 elderly) completed two versions of the negative priming paradigm (identification and localization), and two variants of the directed forgetting paradigm (listwise and itemwise). Two tasks of the Wechsler Intelligence Test with high loadings on general fluid intelligence (Gf) served as validation criteria. Results revealed task-specific and speed-independent inhibitory deficits in the elderly (lower negative priming in both paradigms; more intrusions in the directed forgetting tasks), as well as higher levels of repetition priming. Significant correlations between measures of inhibition and the Wechsler scores were found in both age groups. Results support the view of multiple inhibitory-like capabilities that play a central role in the decline of higher-order cognitive functions in old age.     

An exploration of genetic g: Hierarchical factor analysis of cognitive data from the western reserve twin project

Hierarchical factor analyses involving Schmid-Leiman transformations (Schmid & Leiman, 1957) were conducted on specific cognitive abilities data collected in a sample of 148 identical (MZ) and 135 same-sex fraternal (DZ) twin pairs. Two main questions were addressed: First, are genetic influences on specific cognitive abilities simply a reflection of their g loading, or are different sets of genes affecting separate abilities? Second, to the extent that specific cognitive abilities are affected by common genetic variance, how similar is the common genetic factor to a phenotypic factor reflecting g? Model fitting results suggest that genetic influences on specific abilities are a reflection of both general intelligence and genetic influences specific to separate abilities and that loadings on the common genetic factor are more highly correlated with phenotypic g loadings than are common environmental factor loadings.     

AULA virtual reality test as an attention measure: Convergent validity with Conners’ Continuous Performance Test

The majority of neuropsychological tests used to evaluate attention processes in children lack ecological validity. The AULA Nesplora (AULA) is a continuous performance test, developed in a virtual setting, very similar to a school classroom. The aim of the present study is to analyze the convergent validity between the AULA and the Continuous Performance Test (CPT) of Conners. The AULA and CPT were administered correlatively to 57 children, aged 6–16 years (26.3% female) with average cognitive ability (IQ mean = 100.56, SD = 10.38) who had a diagnosis of attention deficit/hyperactivity disorder (ADHD) according to DSM-IV-TR criteria. Spearman correlations analyses were conducted among the different variables. Significant correlations were observed between both tests in all the analyzed variables (omissions, commissions, reaction time, and variability of reaction time), including for those measures of the AULA based on different sensorial modalities, presentation of distractors, and task paradigms. Hence, convergent validity between both tests was confirmed. Moreover, the AULA showed differences by gender and correlation to Perceptual Reasoning and Working Memory indexes of the WISC-IV, supporting the relevance of IQ measures in the understanding of cognitive performance in ADHD. In addition, the AULA (but not Conners’ CPT) was able to differentiate between ADHD children with and without pharmacological treatment for a wide range of measures related to inattention, impulsivity, processing speed, motor activity, and quality of attention focus. Additional measures and advantages of the AULA versus Conners’ CPT are discussed.     

Spatial memory in rats: A cross validation study

Two experiments were performed to investigate whether two measures of spatial memory, working memory (WM) and reference memory (RM), can be generalized over learning situations. In the first experiment, outbred WU rats were used; in the second four inbred strains. In both experiments rats were given 50 training trials in both a holeboard and a high-sided radial maze: 4 out of 16 holes and 4 out of 8 arms were baited. The number of WM (revisits to baited holes/arms) and RM (visits and revisits to never baited holes/arms) errors were calculated for 5 blocks of 10 trials; odd-even reliabilities were determined for the last 20 trials and were shown to be satisfactory for both measures in both types of apparatus. Error-decrements were analyzed by trend components. For both WM and RM, simple and canonical correlations were determined between means and significant trends in maze and holeboard as a test for construct validity; in both experiments r's and R_c's were very low. It was concluded that the concepts WM and RM are not validly generalizable over tests.     

Toward a Model of Neuropsychological Activity

The main purpose of this research was to establish the intercorrelations existing among different psychological and neuropsychological test scores in a normal and homogenous population. A second purpose was to attempt further step in the component analysis of cognitive activity measured by means of neuropsychological tests. A comprehensive neuropsychological test battery was assembled and individually administered to a 300-subject sample, aged 17–25 years-old. All of them were right-handed male university students. The battery included some basic neuropsychological tests directed to assess language, calculation abilities, spatial cognition, praxic abilities, memory, perceptual abilities, and executive functions. In addition, the Wechsler Adult Intelligence Scale was administered. Forty-one different scores were calculated. Correlations among the different test scores were analyzed. It was found that some of the tests presented a quite complex intecorrelation system, whereas other tests presented few or no significant correlations. Mathematical ability tests and orthography knowledge represented the best predictors of Full Scale IQ. A factor analysis with varimax rotation disclosed five factors (verbal, visuoperceptual, executive function, fine movements, and memory) accounting for 63.6% of the total variance. Implications of these results for a neuropsychological model about brain organization of cognition were analyzed.