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PubMed2003

Pre-placement screening in international adoption.

BACKGROUND: The number of child adoptions from abroad is increasing, but the adverse living conditions of these children prior to the adoption raise questions on their medical and neurodevelopmental status, particularly since there are no guidelines for pre- or post-adoption medical evaluation. OBJECTIVES: To describe the condition of a cohort of young children who were candidates for adoption in East European orphanages and foster homes, and to determine those attributes associated with a family's decision to adopt or refuse a particular child. METHODS: Eighty-two young children, median age 11 months, were evaluated by Israeli pediatricians in Eastern Europe between 3 weeks and 6 months prior to their adoption. The evaluation consisted of comprehensive medical and neurodevelopmental testing on site using a battery of standardized assessment tools, and observation of free play and social interactive behaviors recorded on videotape. Laboratory tests included complete blood count, chemistries, serology screening, and metabolic and genetic testing. RESULTS: The children were growth-retarded. Medical problems were classified as resolved (pneumonia and diarrhea) in 32.8%; or ongoing, such as hepatitis B and C, failure to thrive, organomegaly, and visual and hearing disorders, in 14.8%. Neuromotor status was grossly abnormal in 13.4%. Twenty-two percent of the children were rejected for adoption by families in Israel. Factors associated with the adoption decision were performance skills on developmental testing (P = 0.0001), present medical status (P = 0.002), and weight (P = 0.016). CONCLUSIONS: Pre-placement comprehensive screening of children eligible for foreign adoption, which includes developmental screening, helps to identify a wide variety of strengths and impairments in a child's background before the adoption procedure is finalized. A family's decision to adopt or not was associated with the child's performance on Bayley Scales, weight, and current medical status, but not with language delays, serious past medical history or suspect family background.

Adoption↗

PubMed1998

Using functional magnetic resonance imaging to understand the mechanisms of consciousness.

BACKGROUND: In order to elucidate mental functions that subserve human consciousness, brain activation was investigated in 12 normal, right-handed volunteers who performed tasks of selective attention, working memory, and sensorimotor coordination during the collection of multislice echoplanar functional magnetic resonance images. HYPOTHESIS: These functions are located in (and controlled by) distinct anatomical regions that can be identified by functional magnetic resonance imaging techniques. METHODS: In each subject, 100 10-slice data sets were acquired using a 1.5-T scanner and the blood oxygenation level dependent contrast technique. Time-series regression modeling estimated power in the magnetic resonance signal during the on/off phases of task performance. Comparison between subjects was made possible by the transformation of each data set into standard Talairach space. RESULTS: Activation maps were based on the median value of the fundamental power quotient at each voxel. Results showed the activation of prefrontal and parasagittal cortices in both the selective attention and working memory tasks, but they also revealed activation in both insular cortices and the posterior cingulate gyri. CONCLUSIONS: The results provide evidence for structures in the anterior right hemisphere and left medial frontal lobe for attentional tasks, although there appears to be an engagement of a widespread network of anterior brain structures, possibly with the inhibition of some posterior regions, during task performance. The sensorimotor coordination task showed activation regions similar to those seen in selective attention. Once learned, this task probably demands attention rather than overt conscious motor control. Clearly, the functions of attention, working memory, and sensorimotor coordination are not located in single, discrete brain areas. However, interactions and interplay between related areas were demonstrated, giving supporting evidence that complex mental operations rely on the coordinated activity of widely distributed brain regions that contribute to neural networks.

Adult↗

PubMed1995

Work performance of Chinese cycle haulers: controlled field experiments in normal work conditions.

Forty-five male Chinese cycle haulers performed a controlled field experiment under mild winter conditions. The objective was to gain insight into factors that affect work performance. Each man hauled the same 481-kg load around a Beijing street course of 14.18 km. The experiment was a measured sample of the same work they do routinely, on the same roads, using similar human powered hauling cycles (modified only enough to carry observers and instruments). The course was completed at a mean speed of 10.4 kph and mean time of 84.2 min. While there was considerable variation in individual pace and in pace change during work, the haulers performed at relatively high output in reference to their capacities. Mean heart rate was 156.8 +/- 16.1 bpm, 83.9% of maximum. The men had average body build and were average in size for the general Chinese population (X stature = 169.7 cm) although they showed relatively high aerobic capacity (determined in laboratory tests). Performance levels during experiments appear to match habitual work patterns, and self-pacing emerged as a major behavioral finding of this research. Speed, a primary index of job performance, showed significant correlation to heart rate, VO2max, variation in windchill, self-reported health and other variables, with a multiple regression coefficient of 0.811. Similar patterns were seen for heart rate relative to speed, except that physical size, education, and other behavioral variables were also predictors.

Adult↗

PubMed2004

Adaptive strategy changes as a function of task demands: a study of car drivers.

When drivers perform additional tasks while driving, research shows conflicting results: primary driving performance may deteriorate but adaptive changes such as reducing driving speed have also been noted. We hypothesized that the nature of the secondary task may be important: drivers may give more priority to tasks that serve goals of the driving task itself, for example route finding, than tasks not directly relevant for driving, for example tuning the radio. The main objective of the present driving simulator study was to test this hypothesis. Twenty subjects performed two different subsidiary tasks while driving through two levels of traffic density: a working memory (WM) task and a map reading (MAP) task. It was hypothesized that in high task demand situations, the WM task, irrelevant for the driving task, would be neglected more than the MAP task. The results confirmed the hypothesis: in MAP conditions, the WM task was indeed neglected, but map reading resulted in more swerving, indicating that the subjects looked at the map despite the high task demands. It is concluded that drivers will be highly motivated to get route information, and RG systems should therefore present their information in a readily understandable format.

Adult↗

PubMed1996

Human resource departments and hospital labor strategies.

Recently hospitals have increased their use of external labor sources, contracting many traditional functions such as pharmacy and emergency to outside labor providers. Use of external labor sources often means that traditional human resource functions such as screening, hiring, and training are performed by the external labor provider, potentially reducing the value of the HR function. Using financial and staffing data gathered by the California Statewide Health Planning and Development Office during the period 1976 to 1989, this study explores the relationship between the size of HR functions and the utilization of contingent labor.

California↗

PubMed2003

Study on performance following Key Performance Indicators for trauma care: Khon Kaen Hospital 2000.

This study was conducted in 2000-2001 in order to improve the quality of trauma care by establishing the Key Performance Indicators (KPIs) as a guideline in providing trauma care service and to study the personnel's performance following 27 indexes of KPIs for trauma care in Khon Kaen Hospital. After the implementation of the KPIs by the method of participatory action research (PAR), the trauma preventable death rate was decreased to 1.3 per cent which was statistically different from the preventable death rate in 1997 (2.0%).

Emergency Medical Services↗

PubMed1995

Without a vision, a business may perish.

The process described is not only viable for a company, but also can be used by any group that is gathered to perform any task. The process serves to explore strengths and weaknesses so the group can use one and shore up the other. It looks at the outside forces that may affect the work and allows the group to place its effort in the areas it can influence. By looking at what is or about to occur, the process may be able to create synergism or prevent disaster. A vision or direction statement that many if not all had some input into is easier to understand and support. Referral to these benchmarks or compass points makes the journey easier.

Commerce↗

PubMed2005

Enduring the shipboard stressor complex: a systems approach.

A high incidence of physiological and psychological stressors characterizes the maritime work environment in many segments of the commercial maritime industry and in the military. Traditionally, crewmembers work embedded in a complex of stressors. Stressors rarely act independently because most occur concurrently, simultaneously taxing physical and mental resources. Stressors such as extreme environmental temperatures, long work hours, heavy mental and physical workload, authoritative leadership, isolation from family and loved ones, lack of exercise, and unhealthy diets often combine to degrade crewmember health and performance, particularly on long voyages. This complex system of interacting stressors affects the ability of maritime crewmembers to maintain adequate levels of alertness and performance. An analytical systems approach methodology is described here as a viable method to identify workplace stressors and track their systemic interactions. A systems-based program for managing the stressor complex is then offered, together with the empirical research supporting its efficacy. Included is an example implementation of a stressor-control program aboard a U.S. Coast Guard cutter.

Adaptation, Physiological↗

PubMed2006

Age-related changes in brain activity across the adult lifespan.

A number of theories have emerged to explain the well-studied changes in memory that occur with age. Many of these theories invoke mechanisms that have the potential to affect multiple cognitive domains, in addition to memory. Such mechanisms include alterations in attentional or inhibitory function, or dysfunction of specific brain areas, such as the frontal lobes. To gain insight into these mechanisms, we used functional magnetic resonance imaging to examine brain activity during encoding and recognition tasks in young, middle-aged, and older adults to identify correlations between age and brain activity across the various tasks. The goal was to see whether these correlations were task-specific or common across tasks, and to determine whether age differences emerged in a linear fashion over the adult years. Across all memory tasks, at both encoding and recognition, linear increases of activity with age were found in areas normally decreased during task performance (e.g., medial frontal and parietal regions), whereas activity in regions with task-related activation (e.g., dorsolateral prefrontal cortex) decreased with age. These results suggest that there is a gradual, age-related reduction in the ability to suspend non-task-related or "default-mode" activity and engage areas for carrying out memory tasks. Such an alteration in the balance between default-mode and task-related activity could account for increased vulnerability to distraction from irrelevant information, and thereby affect multiple cognitive domains.

Adult↗

PubMed2004

Deaf children's use of phonological coding: evidence from reading, spelling, and working memory.

Two groups of deaf children, aged 8 and 14 years, were presented with a number of tasks designed to assess their reliance on phonological coding. Their performance was compared with that of hearing children of the same chronological age (CA) and reading age (RA). Performance on the first task, short-term recall of pictures, showed that the deaf children's spans were comparable to those of RA controls but lower than CA controls. For the older deaf children, short-term memory span predicted reading ability. There was no clear evidence that the deaf children were using phonological coding in short-term memory when recall of dissimilar items was compared with recall of items with similarly sounding names. In the second task, which assessed orthographic awareness, performance of the deaf children was similar to that of RA controls although scores predicted reading level for the deaf children but not the hearing. The final task was a picture spelling test in which there were marked differences between the deaf and hearing children, most notably in the number of spelling refusals (which was higher for the deaf children in the older group than their RA controls) and the percentage of phonetic errors (which was considerably lower for both groups of deaf children than for any of the hearing controls). Overall these results provide support for the view that deaf children place little reliance on phonological coding.

Adolescent↗

PubMed2004

Language influences on verbal short-term memory performance in Down syndrome: item and order recognition.

Down syndrome is associated with severe deficits in language and verbal shortterm memory, but the causal relationship between these deficits is unclear. The current study therefore investigated the influence of language abilities on verbal short-term memory performance in Down syndrome. Twenty-one individuals with Down syndrome and 29 younger typically developing children were tested on memory for words and nonwords using 2 immediate recognition tasks: an order memory task that was a relatively pure measure of verbal short-term memory and an item memory task that was more sensitive to language ability. Despite having superior vocabulary knowledge to the typically developing children, individuals with Down syndrome were impaired on both order and item tasks. This impairment was particularly marked on the item task, where individuals with Down syndrome showed an atypically large lexicality effect. These results are interpreted in terms of an underlying verbal short-term memory deficit in Down syndrome that is compounded by poor phonological discrimination abilities.

Acoustic Stimulation↗

PubMed2001

Age related changes in inhibitory control as measured by stop signal task performance.

A modified version of the stop signal task (suitable for use with very young children) was administered to a pre primary school group of children (<5 years, 6 months); a young primary group (5 years, 7 months to 7 years, 6 months); a mid primary group (7 years, 7 months to 9 years, 6 months) and a group of adults. Significant age differences in the ability to inhibit responding were found. These results highlight the need for measures of response inhibition which are appropriate for use with very young children, when the first signs of inhibitory skills are emerging. It is also imperative that such measures allow the assessment of skills across a broad range of age groups in order to comprehensively monitor their development.

Adolescent↗

PubMedDate not supplied

[The development of work regimens for miners in high-temperature coal mine faces for the prevention of heat-related lesions].

In an in-plant setting, the level of functional tension of an organism is almost half determined with a high degree of reliability by a character of ergothermal loading. With the work performed becoming harder and more strenuous by one unit of measuring, the air temperature changing by 1 degree C relative to the maximum allowable level (MAL), and labour time coefficient by 0.1, changes in heart rate amount to 9.7, 2.5 and 2.1 beats/min respectively. Maintenance of the functional state of an organism at an adequate level is achieved through cutting the work shift time by 30 min or increasing the normative time for having a rest ca twice as much relative to the basic level per each degree of the temperature increments above the MAL.

Adult↗

PubMed2006

CPR training and CPR performance: do CPR-trained bystanders perform CPR?

OBJECTIVES: To determine factors associated with cardiopulmonary resuscitation (CPR) provision by CPR-trained bystanders and to determine factors associated with CPR performance by trained bystanders. METHODS: The authors performed a prospective, observational study (January 1997 to May 2003) of individuals who called 911 (bystanders) at the time of an out-of-hospital cardiac arrest. A structured telephone interview of adult cardiac-arrest bystanders was performed beginning two weeks after the incident. Elements gathered during interviews included bystander and patient demographics, identifying whether the bystander was CPR trained, when and by whom the CPR was performed, and describing the circumstances of the event. If CPR was not performed, we asked the bystanders why CPR was not performed. Logistic regression was used to calculate odds ratios and 95% confidence intervals (95% CI) for factors associated with CPR performance. RESULTS: Of 868 cardiac arrests, 684 (78.1%) bystander interviews were completed. Of all bystanders interviewed, 69.6% were family members of the victims, 36.8% of the bystanders had more than a high-school education, and 54.1% had been taught CPR at some time. In 21.2% of patients, the bystander immediately started CPR, and in 33.6% of cases, someone started CPR before the arrival of emergency medical services (EMS). Important overall predictors of CPR performance were the following: witnessed arrest (OR = 2.3; 95% CI = 1.4 to 3.8); bystander was CPR trained (OR = 6.6; 95% CI = 3.5 to 12.5); bystander had more than a high-school education (OR = 2.0; 95% CI = 1.2 to 3.1), or arrest occurred in a public location (OR = 3.1; 95% CI = 1.7 to 5.8). These variables were significant predictors of CPR performance among CPR-trained bystanders, as was CPR training within five years (OR = 4.5; 95% CI = 2.8 to 7.3). Common reasons that the CPR-trained bystanders cited for not performing CPR were the following: 37.5% stated that they panicked, 9.1% perceived that they would not be able to do CPR correctly, and 1.1% thought that they would hurt the patient. Surprisingly, only 1.1% objected to performing mouth-to-mouth resuscitation. CONCLUSIONS: A minority of CPR-trained bystanders performed CPR. CPR provision was more common in CPR-trained bystanders with more than a high-school education and when CPR training had been within five years. Previously espoused reasons for not doing CPR (mouth-to-mouth, infectious-disease risk) were not the reasons that bystanders cited for not doing CPR. Further work is needed to maximize CPR provision after CPR training.

Adult↗

PubMedDate not supplied

Evaluating driving performance of outpatients with Alzheimer disease.

BACKGROUND: Alzheimer disease (AD) is a progressive disease, with multiple physiologic, psychologic, and social implications. A critical issue in its management is when to recommend restrictions on autonomous functioning, such as driving an automobile. This study evaluates driving performance of patients with AD and its relation to patient scores on the Mini-Mental State Exam (MMSE). METHODS: This study compared 29 outpatients with probable AD with 21 age-matched control participants on an interactive driving simulator to determine how the two groups differed and how such differences related to mental status. RESULTS: Patients with AD (1) were less likely to comprehend and operate the simulator cognitively, (2) drove off the road more often, (3) spent more time driving considerably slower than the posted speed limit, (4) spent less time driving faster than the speed limit, (5) applied less brake pressure in stop zones, (6) spent more time negotiating left turns, and (7) drove more poorly overall. There were no observed differences between AD patients and the control group in terms of crossing the midline and driving speed variability. Among the AD patients, those who could not drive the simulator because of confusion and disorientation (n = 10) had lower MMSE scores and drove fewer miles annually. Those AD patients who had stopped driving also scored lower on their MMSE but did not perform more poorly on the driving simulator. Factor analysis revealed five driving factors associated with AD, explaining 93 percent of the variance. These five factors correctly classified 27 (85 percent) of 32 AD patients compared with the control group. Of the 15 percent who were improperly classified, there were three false positives (control participants misclassified as AD patients) and two false negatives (AD patients misclassified as control participants). The computed total driving score correlated significantly with MMSE scores (r = -.403, P = 0.011). CONCLUSION: Driving simulators can provide an objective means of assessing driving safety.

Aged↗

PubMed1975

Labor performance measurement in visual inspection and packing operations.

A methodological procedure for identifying and measuring the variables involved and their impact on labor performance in manual inspection and sorting operations is presented. The applicability of the procedure is shown as it applies in an analysis of canning asparagus spears. Worker output rates for any given spear size index tended to decrease along successive work stations, with exceptions where there were changes in proportion to specific sizes available. The canning performance was influenced by interactions among the size, positional line-load, and worker position variables as the product moved along the supply conveyer. Because linear regression equations computed to estimate the number of can per canner per minute were not effective in indicating the effect of spear size distribution nor that of interactions among other relevant variables, a more comprehensive model was developed to estimate cans per worker per minute as a function of line-load, worker position, and three binary variables representing interactions between these variables and spear-size indices. The results of this and similar studies may be used as a basis for suggesting better planning of raw product delivery schedules, introduction of innovative processes, and crew reorganization.

Decision Making↗

PubMed2004

Speech-based E-mail and driver behavior: effects of an in-vehicle message system interface.

As mobile office technology becomes more advanced, drivers have increased opportunity to process information "on the move." Although speech-based interfaces can minimize direct interference with driving, the cognitive demands associated with such systems may still cause distraction. We studied the effects on driving performance of an in-vehicle simulated "E-mail" message system; E-mails were either system controlled or driver controlled. A high-fidelity, fixed-base driving simulator was used to test 19 participants on a car-following task. Virtual traffic scenarios varying in driving demand. Drivers compensated for the secondary task by adopting longer headways but showed reduced anticipation of braking requirements and shorter time to collision. Drivers were also less reactive when processing E-mails, demonstrated by a reduction in steering wheel inputs. In most circumstances, there were advantages in providing drivers with control over when E-mails were opened. However, during periods without E-mail interaction in demanding traffic scenarios, drivers showed reduced braking anticipation. This may be a result of increased cognitive costs associated with the decision making process when using a driver-controlled interface when the task of scheduling E-mail acceptance is added to those of driving and E-mail response. Actual or potential applications of this research include the design of speech-based in-vehicle messaging systems.

Accidents, Traffic↗

PubMed1994

Progression of kaolin-induced hydrocephalus and changes in performance of operant tasks by rats.

The behavior of rats with progressive hydrocephalus was examined to detect early neurological deterioration. Kaolin solution was injected into the cisterna magna of 10 of 17 anesthetized 8-week-old male rats (day 0), and saline in the other 7 rats (control group). Reaction time (RT, sec) and error ratio (ER, %) of unanesthetized rats escaping from electrical stimuli toward a nonstimulated sheet within a box were recorded daily from day 4 until autopsy after 4 weeks. Three rats in the kaolin group died in acute stage. Rats were assigned to either severe (S) (n = 4) or moderate (M) (n = 4) group according to the degree of ventricular dilatation at autopsy. The RTs prolonged and ERs increased in the kaolin group and they reached their minimum values. Values after the minimum RT value on day 12 in the M-group and 22 in the S-group during the chronic stage were compared with those in the controls, which decreased throughout the experiments (P < 0.03). In all animals in the S-group RT was prolonged each day with a linear regression (P < 0.005), although ER was decreased (0.69 > P > 0.23). In 3 rats and in another rat in the M-group RT was prolonged (P < 0.04 and P = 0.19) and ER was decreased in 3 rats (two: P = 0.41; one: P = 0.01) and increased in one (P = 0.55). In conclusion, deteriorated motor function is more important for early diagnosis in progressive hydrocephalus than behavioral symptoms.

Animals↗