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PubMed2006

The contribution of health discussion groups with students to campus health promotion.

Based on the idea of implementing health promotion in the university setting, this project is aimed at identifying determinants of health and well-being in the working and living environment of students and at developing targeted health interventions. The approach of health discussion groups is a well-established tool in workplace health promotion to enable participation and empowerment. This concept was innovatively applied and evaluated with the student body. There were seven sessions held at the University of Bielefeld with students from five different areas, a representative of the university management and a representative from the compulsory accident assurance. Process evaluation was done through standardized questionnaires and guided interviews with the participants while its impact was assessed in a follow-up period of 3 years by the amount of effects. Data included 11 distinct topics from the areas of study conditions, learning and their living environment with a total of 46 ideas for health-promoting actions. The process evaluation showed highly positive results, both in quantitative as well as qualitative approaches. Critical points were the resistances of students to participate in health discussion groups and the low confidence of students in the implementation of the proposed measures. The follow-up after 3 years showed that 11% of proposed actions could not be implemented, while 43% have resulted in recommendations for policy guidelines, 20% were fully implemented and 26% is still in progress. In conclusion, the health discussion group proved to be a useful instrument for student participation in university-based health promotion. Special emphasis should be given towards decreasing barriers for participation. The implementation of the proposed actions is highly depending on well-established structures of health promotion, such as a steering committee, and the commitment of the university management.

Communication↗
PubMed2001

Proprioceptive feedback is reduced during adaptation to a visuomotor transformation: preliminary findings.

Adapting movements in relation to visual feedback is a ubiquitous characteristic of sensorimotor control and involves the integration of multiple sources of sensory information. We recorded sensory feedback from muscle spindle afferents during visuomotor adaptation while subjects performed an aiming task to investigate whether the activity of the muscle spindles was modulated by the fusimotor system under these learning conditions. None of the muscle spindles showed an increase in activity, rather in 83% of the trials the firing rates were decreased. These preliminary results suggest that the CNS reduces the sensory signals arising from muscle spindles perhaps as a means of resolving the conflict between visual and proprioceptive feedback during the task.

Action Potentials↗
PubMed2006

Heads up on cerebral bleeds.

Bleeding in the brain can be difficult to pinpoint and may mimic other conditions. Learn how to help your patient get an accurate diagnosis and appropriate treatment quickly.

Journal Article↗
PubMed2004

Are children born after assisted reproductive technology at increased risk for adverse health outcomes?

As assisted reproductive technologies (ARTs) are increasingly used to overcome infertility, there is concern about the health of the children conceived. The empirical evidence for associations with outcomes related to child health is variable and should be evaluated with consideration of methodological shortcomings. Currently, there is convincing evidence that ART treatment may increase the risk of a few outcomes. Experimental laboratory studies document that various constituents in culture media affect various embryo characteristics both positively and negatively. Multiple-gestation pregnancy and birth are increased with ART, both because of multiple embryo transfer and embryo splitting. There is evidence of an increase in chromosomal abnormalities among pregnancies conceived using intracytoplasmic sperm injection and low birth weight and preterm delivery among singletons conceived with all types of ART; however, there remains uncertainty about whether these risks stem from the treatment or the parental infertility. For some outcomes, data of an increased risk with ART are suggestive at best largely because of lack of purposeful study of sufficient size and scope. These include specific perinatal morbidities, birth defects, developmental disabilities, and retinoblastoma. The evidence for an association between ART and spontaneous abortion is inconsistent and weak. There is inconclusive evidence that ART may be associated with genetic imprinting disorders. For childhood cancer, chronic conditions, learning and behavioral disorders, and reproductive effects there is insufficient empirical research to date, but given the data for more proximal outcomes, these outcomes merit further study. Future research needs to address the unique methodological challenges underlying study in this area.

Abortion, Spontaneous↗
PubMed1999

Dynamic updating in DIAS-NIDDM and DIAS causal probabilistic networks.

Diabetes advisory system (DIAS) is a decision support system, which has been developed to provide advice on the amount of insulin injected by subjects with insulin-dependent diabetes mellitus (IDDM). DIAS employs a temporal causal probabilistic network (CPN) to implement a stochastic model of carbohydrate metabolism. The CPN network has recently been extended to provide also advice to subjects with noninsulin-dependent diabetes mellitus (NIDDM). However, due to increased complexity and size of the extended CPN the calculations became unfeasible. The CPN network was, therefore, simplified and a novel approach employed to generate conditional probability tables. The principles of dynamic CPN's were adopted and, in combination with the method of conditioning, learning, and forecasting, were implemented in a time- and memory-efficient way. An evaluation using experimental data was carried out to compare the original and revised DIAS implementations employing data collected by patients with IDDM, and to assess the a posteriori identifiability of model parameters in patients with NIDDM.

Adult↗
PubMed2006

The role of the student: salutogenic or pathogenic?

Associations between sense of coherence (SOC) and school-related resources (supportive school environment, adequate learning conditions) and stress (pressure of schoolwork, bored of school) were explored in a representative sample of 4116 Norwegian school adolescents, aged 11, 13 and 15 years. The students participated in the World Health Organization Cross-National Survey 'Health Behaviour in School-Aged Children 1997/98 (HBSC)'. Multiple linear regression analyses were applied. In unadjusted analyses, all resources and stress factors were significantly related to SOC. In analyses adjusted for all these factors, support from teacher was the only variable that did not remain significant. The strongest and most adverse association with SOC was seen in the relation with feeling pressured by schoolwork among both genders. The next strongest associations were found with support from peers and adequate expectations. In general, the associations with SOC were stronger among girls than boys, but a similar tendency was found for both genders. Implications for school health promotion are discussed.

Adolescent↗
PubMed2006

Activation of preexisting and acquired face representations: the N250 event-related potential as an index of face familiarity.

Electrophysiological studies using event-related potentials have demonstrated that face stimuli elicit a greater negative brain potential in right posterior recording sites 170 msec after stimulus onset (N170) relative to nonface stimuli. Results from repetition priming paradigms have shown that repeated exposures of familiar faces elicit a larger negative brainwave (N250r) at inferior temporal sites compared to repetitions of unfamiliar faces. However, less is known about the time course and learning conditions under which the N250 face representation is acquired. In the familiarization phase of the Joe/no Joe task, subjects studied a target "Joe" face ("Jane" for female subjects) and, during the course of the experiment, identified a series of sequentially presented faces as either Joe or not Joe. The critical stimulus conditions included the subject's own face, a same-sex Joe ( Jane) face and a same-sex "other" face. The main finding was that the subject's own face produced a focal negative deflection (N250) in posterior channels relative to nontarget faces. The task-relevant Joe target face was not differentiated from other nontarget faces in the first half of the experiment. However, in the second half, the Joe face produced an N250 response that was similar in magnitude to the own face. These findings suggest that the N250 indexes two types of face memories: a preexperimentally familiar face representation (i.e., the "own face" and a newly acquired face representation (i.e., the Joe/Jane face) that was formed during the course of the experiment.

Adolescent↗
PubMed1991

The boundaries of attention deficit disorder.

This report examines distinctions and interrelationships among attention deficit disorder (ADD) and two closely related conditions: learning disability (LD) and oppositional/conduct (O/C) disorder. To evaluate our hypothesis that some of the difficulty in resolving the relationship between ADD and, particularly, O/C may reflect the consequences of selective referral patterns, we studied groups of children diagnosed as ADD from different referral sources. Results suggest that referral bias does exist and that children referred to mental health settings differ from those referred to pediatricians, child neurologists, or psychologists. Because of the nature of the subjects referred to mental health services, nonrepresentative associations may emerge. Rather than being considered as prototypical of all children with attention disorder, children referred to mental health facilities may represent simply an extreme of the continuum of ADD. Evidence suggests that many children with ADD will be represented by those referred primarily for attentional deficits and learning problems, rather than those with inattention, hyperactivity, or aggression referred for child psychiatric evaluation.

Adolescent↗
PubMed1993

Comparing two modes of teaching a question-answering strategy for enhancing reading comprehension: didactic and self-instructional training.

This study investigated the comparative efficacy of two instructional approaches--didactic teaching and self-instructional training--in teaching average and poor readers a comprehension question-answering strategy. Forty-five average students and 45 poor readers from Grades 5 and 6 participated. These 38 girls and 52 boys were equally and randomly assigned to one of three treatment conditions: didactic teaching of the strategy, self-instruction, or control (no training). Students in the first two treatment conditions learned a mnemonic strategy ("Here," "Hidden," and "in my Head") to indicate question-answer relationships that are text explicit, text implicit, or script implicit, respectively. Essentially, the 3H mnemonic cued students to use appropriate text and/or knowledge-base information in answering comprehension test questions. In addition, students in the self-instruction group learned three self-questions to guide their use of the 3H strategy. Specifically, the self-questions focused students' attention on the task, provided a basis for decision making concerning the categorization of comprehension test questions, and reminded students to check their answers. The results indicated that both didactic teaching and self-instructional training of the strategy effected significant improvements in students' reading comprehension performance. However, self-instructional training was more effective in enhancing and maintaining students' reading comprehension performance than didactic teaching. Moreover, results from the oral questionnaire indicated that the 3H strategy training increased students' general meta-cognitive knowledge. Lastly, of the 60 trained students, 52 wrote that they would encourage other children to learn the 3H strategy. Thus, the response to strategy learning was clearly positive.

Attention↗
PubMed2004

Gender differences in memory for the appearance of others.

Five studies investigated gender differences in the accurate recall of the appearance of others. The greater interpersonal orientation and interpersonal sensitivity of women were predicted to give women an advantage over men in appearance accuracy. Under both directed- and incidental-learning conditions, women more accurately recalled information concerning the appearance of their social targets than did men, participants' memory for the appearance of female targets was more accurate than it was for male targets, and neither gender was found to be a relative advantage in recalling the appearance of same-gender targets. The motivational and knowledge-based factors that might underlie a gender difference in appearance accuracy are discussed.

Adult↗
PubMed2001

Responses of the densely hemiplegic upper extremity to bilateral training.

OBJECTIVE: Recovery of movement in the densely hemiplegic upper extremity remains a problem after stroke. This study aimed to determine whether movement recovery could be improved in the hemiplegic arm with bilateral isokinematic training. METHODS: Within and between groups, planned comparisons investigated the effects of bilateral training on attempts at two movements by subjects with acute and chronic problems with one and two bilateral practice phases. Electromyographic (EMG) activity of middle deltoid and extensor carpi radialis longus in the hemiplegic arm was recorded during unilateral and bilateral isometric shoulder abduction and wrist extension. RESULTS: Small increases in muscle activity were demonstrated by both experimental and control subjects during most bilateral practices in both actions. However, these increases were not significantly different from the previous unilateral trial, and the bilateral effect failed to generalize to subsequent trials. Previous studies with less densely hemiplegic subjects had demonstrated generalization of improvements in movement patterns with bilateral training to unimanual actions of the densely hemiplegic arm. CONCLUSIONS: Extensive lesions may limit brain reorganization and recover of dense hemiplegia after stroke. Nonetheless, on the basis of findings from other studies in which functional improvements occurred in both acute and chronic severely stroke-affected subjects, outcome forecasting for the hemiplegic upper extremity should only eventuate after provision of practice under optimal learning conditions.

Acute Disease↗
PubMed1985

Lorazepam in cancer patients treated with cisplatin: a drug having antiemetic, amnesic, and anxiolytic effects.

There currently is no pharmacologic approach to the problem of anticipatory nausea and vomiting (ANV). Lorazepam (Ativan, Wyeth Laboratories, Philadelphia) is an interesting candidate drug if it could block the recall of the unpleasant events associated with chemotherapy, especially if it also has antiemetic properties. Since ANV is a conditioned (learned) response, it may well depend on a memory imprint of the stimulus. This pilot study was designed to use intravenous lorazepam given before and after cisplatin infusion in 32 patients, and to make detailed measurements of nausea, vomiting, recent memory, anxiety, and sedation as well as toxicity. Satisfactory responses occurred in about 70%, as rated separately both by investigator and patient. Forty-six percent did not even recall receiving chemotherapy, regardless of whether or not they vomited; 80% had no significant anxiety after chemotherapy. Adverse reactions included some cases of perceptual disturbance, urinary incontinence, diarrhea, hypotension, and one case of severe transient amnesia. No long-term adverse effects were noted.

Adult↗
PubMed2006

Rapid topographical plasticity of the visuomotor spatial transformation.

Information about the world is often encoded in the brain as topographic maps. These internal representations are not always static but can have a dynamic nature, allowing for constant adjustments that depend on factors like experience or injury. Recently, it has been shown that areas involved in visuomotor transformations also show topographical organization. These findings suggest that it could be possible to observe plastic modifications in specific parts of the representation in response to a local perturbation that affects only a part of the space that is represented. Here, we tested this hypothesis using an adaptation paradigm with hemiprisms. Our results suggest that, initially, the system tries to modify the visuomotor transformation in the whole spatial representation; however, if feedback is available from both hemifields, the system can perform specific regional topographical realignments. The results also suggest that access to the rearranged visuomotor transformation is independent of eye position, in contrast with previous studies that found a kind of conditional learning. Also, whereas prism adaptation experiments using ballistic movements do not show intermanual transfer of learning, the topographical modification found here is available to both hands. These results provide strong evidence for rapid topographical plasticity that can modify space transformations between two different modalities.

Adolescent↗
PubMed2001

Compulsive checking and selective processing of threatening information.

Threatening stimuli are processed differently from neutral ones by anxious and obsessive-compulsive subjects. In the present research, processing of threatening words was compared with that of neutral words for two groups of Italian students, one with high mean and one with low mean score on Checking, a subscale of the Padua Inventory. Two tests were given, a computerized version of the emotional Stroop task and a later recognition test under incidental learning conditions. The expected interference effect on the Stroop task for those scoring high on Checking was confirmed. These results suggest an association between compulsive checking and bias in the first automatic stages of processing of threatening stimuli.

Adult↗
PubMed2006

Word frequency and the mixed-list paradox in immediate and delayed serial recall.

In free recall tasks, when low- and high-frequency items are mixed within the to-be-remembered lists, the usual recall advantage found for high-frequency words is eliminated or reversed. Recently, this mixed-list paradox has also been demonstrated for short-term serial recall (Hulme, Stuart, Brown, and Morin, 2003). Although a number of theoretical interpretations of this mixed-list paradox have been proposed, researchers have also suggested that it could simply be a result of participant-controlled strategies (M. J. Watkins, LeCompte, and Kim, 2000). The present study was designed to assess whether this explanation could be applied to immediate and delayed serial recall. The results showed that high-frequency words were recalled better than low-frequency words in pure lists, but that this effect was eliminated in mixed lists, whether they were given under intentional or incidental learning conditions. This pattern suggests that the mixed-list paradox cannot be explained by participant-controlled strategies.

Humans↗
PubMed2002

Experiencing a word can prime its accessibility and its associative connections to related words.

This paper reports the results of manipulations of word features for the magnitude of priming effects. In Experiment 1, the printed frequency of the target words and the number of connections among their associates were varied, and during testing participants were given cues and asked to produce the first word to come to mind as rapidly as possible in implicit free association. Priming effects were greater for low-frequency words and for those with many connections among their associates. In Experiments 2 and 3, target words were presented under incidental or intentional learning conditions during study, and the presence of direct preexisting connections from target to cue and from cue to target was varied. Priming effects were greater when either connection was present, with each connection having additive effects. In Experiments 4 and 5, priming effects for indirect links (shared associates and mediators) were examined. The results of these experiments indicate that priming in free association depends on both the general accessibility of the target as a response and the strengthening of direct target-to-cue connections. These findings raise problems for theories that attribute priming only to target accessibility or only to target-to-cue association.

Cues↗