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PubMed2003

ERP correlates of true and false recognition after different retention delays: stimulus- and response-related processes.

Performance and electrophysiological correlates of true and false recognition were examined after short (40 s) and long (80 s) delays. True recognition showed no significant decrease after a long delay, whereas false recognition increased. Early frontal and parietal ERP old/new effects, considered as correlates of familiarity and recollection, were observed across delay for true recognition. No frontal effect occurred in the long delay for false recognition. This absence may arise from weakened memory traces preventing familiarity discrimination for LUREs. Response-related analysis revealed an error-related negativity (ERN) for true and false recognition, assuming that the effect reflects at least partly an internal misrepresentation of the correct response. The larger and topographically different ERNs for false recognition suggest an additional contribution of increased task demands and conditions of high response uncertainty.

Adult↗

PubMed2003

Correspondence between laboratory and ambulatory measures of cardiovascular reactivity: a multilevel modeling approach.

We examined the correspondence between laboratory measures of cardiovascular reactivity (CVR) and within-person changes in cardiovascular activity during the challenges of daily life, after adjustment for posture, activity, and other effects. Healthy adults (n = 335) were administered laboratory measures of CVR along with 6 days of ambulatory blood pressure monitoring and electronic diary reports. Compared with low reactors, high laboratory systolic blood pressure (SBP) reactors showed larger increases in SBP during periods of high task demand or low decisional control in daily life. High diastolic blood pressure (DBP) reactors showed larger increases in ambulatory DBP during situations rated as both low control and high demand. This multilevel modeling approach may enhance our ability to detect the correspondence between laboratory and ambulatory measures of CVR, and to identify the circumstances under which it may be most clearly observed.

Aged↗

PubMed2005

Psychosocial stress and cardiovascular risk: what is the role of daily experience?

We describe an ecological momentary assessment (EMA) protocol designed to measure daily life experiences along several psychosocial dimensions (Social Conflict, Task Demand, Decisional Control, Negative Affect, and Arousal) hypothesized to be relevant for cardiovascular disease risk. In a large community sample, these assessments have been administered in conjunction with ambulatory blood pressure (ABP) monitoring and measures of subclinical cardiovascular disease. Several results have emerged that support the promise of this approach. First of all, each of these dimensions of experience appears to be a trigger for cardiovascular activation, with movement on each scale being associated with significant within-person changes in heart rate and blood pressure in the natural environment. Second, there appear to be individual differences in physiological responsiveness to these dimensions of daily experience, with such differences being associated in some cases with laboratory-based assessments of cardiovascular reactivity, as might be expected. Third, EMA ratings are associated in several instances with (between-person) stable individual differences in ABP readings. And finally, we have found that some of the characteristics defined by our EMA ratings are related to measures of subclinical atherosclerosis. Such effects appear to be mediated, in part, by ABP. The advantages of using EMA measures for capturing the effects of psychosocial stressors are highlighted by comparing the predictive validity of these daily life assessments to traditional global self-reports. We conclude by describing future plans for use of this type of assessment protocol for helping us to characterize psychosocial characteristics relevant to cardiovascular disease risk. Personality and social processes during daily living may have an important impact not only on psychological functioning but also on physical health and disease. In this article we review our recent work involving the assessment of daily experience as a means of better understanding the role of psychosocial stress in cardiovascular disease risk. First, we outline the rationale for our interest in daily experience sampling for examining these processes, and we describe the methods we have adopted for this purpose. Next, we review findings from a recent study in which we have used these approaches to examine the role of psychosocial stress on ABP and atherosclerosis in a community-dwelling sample. We compare our approach to more traditional (global self-report and laboratory-observation) methods for examining these relationships in humans, and we discuss potential future directions for use of daily experience sampling in studies of health and behavior.

Adaptation, Psychological↗

PubMed2003

Do video display units cause visual problems? - a bedside story about the processes of public health decision-making.

PURPOSE: Since the 1980s, it has been common for employers to provide eyesight testing for operators of screen-based equipment (SBE). This practice arose because many SBE operators reported symptoms of visual discomfort at work and there was apprehension that radiation emitted by SBE might be harmful to vision. Visual screening of SBE operators has been encouraged by government guidelines and in some countries, is required by legislation. This paper questions whether this practice should continue. METHOD AND RESULTS: A review of the literature shows: 1. SBE does not emit radiation in sufficient quantity to be harmful and there is no credible epidemiological evidence that work with SBE will damage the eyes; 2. SBE operators often report symptoms of visual discomfort but office workers who do not use SBE also report visual symptoms with the same or slightly lower frequency; 3. about 20 per cent of office workers have some uncorrected defect of vision that can contribute to the occurrence of visual discomfort at work and optometric intervention to correct these defects does reduce the occurrence of visual symptoms. However, defects of vision are not the only cause of visual symptoms at work. Other contributing factors are poor workplace ergonomics and psychosocial stress arising from poor work systems or poor inter-personal relationships at work. CONCLUSIONS: There is no compelling public health justification for requiring vision screening of SBE operators but it could be introduced as one element of a more comprehensive strategy to enhance visual comfort at work. If it is introduced, it should be for all employees engaged in visually demanding tasks, not just SBE users. An alternative to eyesight testing of employees is to encourage but not require employees to obtain eye care privately on their own initiative. This option has the advantage of restoring autonomy to employees to arrange their own eye care. Eyesight testing of employees in vision-critical occupations should be undertaken to ensure safety. In occupations in which there is a risk of eye injury, vision screening should be undertaken to provide a pre-injury record of vision.

Australia↗

PubMed2006

The effect of divided attention on inhibiting the gravity error.

Children who could overcome the gravity error on Hood's (1995) tubes task were tested in a condition where they had to monitor two falling balls. This condition significantly impaired search performance with the majority of mistakes being gravity errors. In a second experiment, the effect of monitoring two balls was compared in the tubes task and a spatial transposition task not involving gravity. Again, monitoring two objects produced impaired search performance in the gravity task but not in the spatial transposition task. These findings support the view that divided attention disrupts the ability to exercise inhibitory control over the gravity error and that the performance drop on this task is not due to the additional task demands incurred by divided attention.

Attention↗

PubMedDate not supplied

General and task-related experiences affect early object interaction.

The effects of 2 weeks of no, general, and task-related enhanced movement experiences on 8- to 12-week-old infants' (N = 30) hand and foot interactions with objects were assessed using standard video and motion analysis. For hand-object interaction ability, general and task experience led to greater success than did no experience, and task experience led to greater success than did general experience. Only general experience led to greater success for foot-object interaction ability. Experiences therefore resulted in differential effects depending on which limbs infants used. The results suggest that different movement experiences can advance infants' earliest object interactions. They also indicate that even early purposeful behaviors result from a complex interplay of experience, current ability, and task demands.

Child Development↗

PubMed1990

Variations in children's conceptualizations of mental retardation as a function of inquiry methods.

This study addresses changes in the responses of third graders to questions about the nature, cause and course of mental retardation under different methods of inquiry. Specifically, do responses vary when the task demands explicit definitions, indirect identification (from a vignette of a functionally retarded but unlabelled youngster), photographic identification, renditions through drawing, or enactment through manipulating a figure on a game board? It was found that the mode of questioning markedly influenced children's portrayal of retardation. Discussion focuses on children's suggestibility (guessing in the service of conformity), greater willingness to be negative when asked to 'show' rather than 'talk', and genuine confusion.

Attitude to Health↗

PubMed1989

The contingent negative variation in psychopaths.

There have been persistent claims that the contingent negative variation (CNV) is absent or greatly attenuated in psychopaths. However, these claims are based on a few studies with serious methodological and diagnostic problems. The present study attempted to avoid these problems. The subjects were male prison inmates divided into psychopaths and nonpsychopaths on the basis of scores on the Psychopathy Checklist. CNV was recorded while the subject performed a forewarned reaction time task with a relatively long interval (6 s) between the warning stimulus and the imperative stimulus. Motivation to perform well was ensured by having reaction times to the imperative stimulus determine how much money would be won or lost on a given trial. The early CNV of psychopaths was significantly larger than was that of the nonpsychopaths. There were no group differences in the late CNV or in reaction time. To the extent that the early CNV reflects processing of the warning stimulus and attention to task demands, the results are consistent with the hypothesis that psychopaths are proficient at focusing attention on events that interest them.

Adult↗

PubMed1994

Developmental dyslexia and attention dysfunction in adults: brain potential indices of information processing.

Event-related brain potentials (ERPs) were recorded from a group of 13 men with severe developmental dyslexia and 15 matched normal controls. Auditory and visual stimuli, presented in separate reaction time tasks of graded difficulty, were used to elicit ERPs. No group differences in P300 were seen under relatively undemanding task conditions. However, as task demands increased, visual P300 was reduced in the dyslexic men as compared with the normal readers. An Abbreviated Conners Parent Rating Scale was used to assess retrospectively childhood symptoms of attention-deficit hyperactivity disorder (ADHD). Additional analyses revealed that the dyslexics with a history of many symptoms of ADHD in childhood (high ADHD) accounted for the group differences in P300; the dyslexics with a history of few or no such symptoms (low ADHD) were indistinguishable from the controls at all electrode sites. Furthermore, whereas the low-ADHD dyslexics showed the same hemispheric asymmetry in auditory P300 as did the controls (right > left), auditory P300 was more symmetrically distributed in the high-ADHD dyslexics. The results are interpreted as suggesting that a distinct brain organization may characterize dyslexic men with a history of concomitant deficits in attention.

Adult↗

PubMed1995

Startle potentiation during anticipation of a noxious stimulus: active versus passive response sets.

The startle reflex response increases during aversive stimulus processing. This study examined whether differing response sets affected startle potentiation during anticipation of an aversive event. Two groups received a noxious noise blast following a 6-s warning cue. Subjects in the active group could press a switch to stop the noise; yoked passive subjects received the same noises with no control. Subjects in a yoked control group heard a soft tone following cue offset. Acoustic startle probes were presented during some of the warning periods and during some of the intertrial intervals. The major finding was that the active and passive groups did not differ in startle potentiation. In comparison with controls, startle reactions for both groups were larger and faster during the warning cue than between trials. The results suggest that the startle reflex indexes defensive response mobilization independently of specific task demands.

Acoustic Stimulation↗

PubMed1996

Affective learning: awareness and aversion.

In two studies, we investigated the influence of aversive and nonaversive reinforcers on startle reactivity, visceral responses, and self-report during Pavlovian conditioning. Furthermore, we assessed how awareness of the stimulus contingencies affect conditioned discrimination in the different response systems. Conditioned potentiation of the startle response was only observed in the context of aversive learning. Moreover, blink potentiation occurred without awareness of the relationship between the conditioned and unconditioned stimulus. In contrast, skin conductance conditioning was independent of the aversiveness of the reinforcer and was only obtained for those individuals who could correctly verbalize the stimulus contingency in a postconditioning recognition test. Cardiac responses varied with the task demands of the situation and covaried with individual response stereotypes.

Adult↗

PubMed1986

Cognitive performance in early Parkinson's disease.

The cognitive, memory and psychomotor performance of 67 patients with Parkinson's disease who had not received any antiparkinson medication was compared with the performance of 43 healthy subjects matched by age and education. The principal impairments in the patients were motor ones, evident in various tests such as general motor slowness and delayed initiation of movement, and they correlated with clinical rigidity and hypokinesia but not with tremor. The performance of the patients was inferior to that of the controls in memory tests involving the processing of information and learning (logical memory, associative learning) but not in less demanding tasks such as the retrieval of numbers. The total disability was due to a combined effect of aging and disease. A decrease of about 15% in the psychomotor and cognitive performance, related to aging alone, can be expected to occur between the ages of 50 and 70. The performance of the patients in memory tests and other tests evaluating cognitive capacity did not correlate either with their motor disability or with their mood. A possibility therefore exists that biological processes behind the cognitive decline and the motor disability are separate, even if they may occur simultaneously.

Adult↗

PubMed1994

Dental health habits of young families from southwestern Finland.

The dental care habits of parents and children as well as the associations of these habits were investigated in a follow-up study conducted in the Southwest of Finland. The background factors of the child's use of night-time juice were also studied. The families of the study were a representative sample of local young families with their first child. The study sample was obtained using stratified randomized cluster sampling and confidential questionnaires. Both the mother's and the father's toothbrushing habits were significantly associated with the child's toothbrushing habits with a cumulative effect. The mother's use of sugar was significantly associated with the child's sugar use habit. Infectious diseases at the age of 9-17 months had an increasing effect on the use of juice at night. Fathers and the youngest mothers, especially, need additional support not only for the demanding task of the upbringing of their child but also for the care of their own teeth.

Adolescent↗

PubMed1989

Influence of age and age-related diseases on olfactory function.

It is clear from this review that olfactory function is markedly altered in old age and in a number of age-related diseases. The deficits appear to be rather general and detectable by several types of olfactory tests. Considerable interindividual variability exists, however, and the physiologic bases of these changes are not clear. In many healthy elderly persons, smell loss appears to occur as a result of one or more causes, including viral insult, cumulated exposure to toxic fumes, head trauma, and calcification of the cribriform plate. Several reviews have appeared suggesting that the olfactory system may be a center of primary involvement in AD. Of particular interest is the hypothesis that environmental agents (related etiologically to the disease process) pass into the central nervous system via the highly active transport mechanisms of the olfactory receptors. This latter notion, although attractive, must be viewed conservatively, as it is possible that the olfactory pathways are simply selectively vulnerable to destruction by various disease processes. This may explain why Huntington's chorea and multiinfarct dementia, in addition to AD and PD, are associated with alterations in smell function. Although it is tempting to assume, as have authors such as Koss et al., that alterations in threshold function reflect peripheral olfactory dysfunction and that alterations in odor identification and other more demanding tasks reflect central olfactory dysfunction, there is little empirical support for such a simple dichotomy. Despite the fact that a peripheral/central distinction is useful in clinical audiology (where threshold loss is commonly associated with CN VIII pathology), an evaluation of the utility of this distinction in olfaction requires further research. The limited data suggest that both identification and detection deficits commonly arise from damage to the olfactory epithelium, even though identification deficits unassociated with detection deficits may occur in some central brain disorders. It is apparent from the studies reviewed in this chapter that considerable progress has been made during the last decade in elucidating the nature and prevalence of olfactory disturbances in elderly patients, as well as in patients with dementia-related diseases.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗

PubMed2002

Scanpaths: the path to understanding abnormal cognitive processing in neurological disease.

Scanpaths, the sequence of saccades and fixations during visual search, provide the means to study a range of cognitive activities: planning, visuospatial attention, and spatial working memory. By measuring scanpaths, we have been able to identify impairment of working memory in patients with spatial hemineglect. Scanpaths during cognitively demanding tasks indicate a defect of working memory in patients with Parkinson's disease. Studies of scanpaths in patients with homonymous hemianopia have provided the means to develop a new strategy for visual rehabilitation.

Attention↗

PubMed1998

Considerations when planning occlusal rehabilitation: a review of the literature.

As one of the most demanding tasks facing the restorative dentist, planning and executing an occlusal rehabilitation should not be undertaken lightly. The stakes are high and failure is costly. Treatment planning decisions should be undertaken on the basis of scientific evidence, where this is available, or on the basis of documented experience where it is not. This review article identifies the major biological and clinical considerations used when planning an occlusal rehabilitation. These include the indications for reorganising the occlusion, the choice of condylar position and occlusal scheme, the implications of and indications for increasing the vertical dimension, replacing missing teeth and the choice of materials. Finally, the literature surrounding the controversial issue of occlusal rehabilitation as a means to treat temporo-mandibular disorders is also reviewed.

Decision Making↗

PubMed1994

Personal constructs associated with tics.

Thirteen subjects experiencing chronic tics kept diaries noting frequency, intensity and degree of control of their tic during their daily routines for one week. Three examples of high-, medium- and low-risk situations were chosen as elements and, using a modified form of Kelly's repertory grid, bipolar constructs were elicited by comparing the three types of situations. Principal dimensions extracted from INGRID analyses differed across individuals but related to three principal areas; self-image, degree of task involvement and type of task demand. Feelings of impatience and frustration frequently accompanied tic onset. Subjects' cognitive evaluations of their tic situations may be important in tic management.

Adult↗

PubMed1987

Anxiety responses to subliminal experience of mild stress.

Two groups of undergraduates (n = 14 in each) matched for level of trait anxiety participated in the experiment. One group (E) was presented with 20 'emotional' words 10 per cent below detection threshold while the other group (N) was presented with 20 emotionally neutral words under the same conditions. Ratings of seven psychological variables were taken before and after stimulation and two psychophysiological measures, heart and respiration rate, were also taken. MANOVA and subsequent ANOVA analyses showed ratings of sweating and anxiety increased in the E group and decreased in the N group following stimulation. Ratings of shaking and muscular tension increased significantly in both groups but the increase was significantly greater in the E group. Ratings of palpitations and difficulty in breathing increased significantly in both groups as did measures of actual heart and respiration rate, but these increases appeared to be an artifact of task demands. It is concluded that manifest anxiety and some features of anxiety having somatic referents can be induced by subliminal experience of mild stress.

Adolescent↗