The nociceptive withdrawal reflex: Normative values of thresholds and reflex receptive fields

Assessments of spinal nociceptive withdrawal reflexes can be used in human research both to evaluate the effect of analgesics and explore pain mechanisms related to sensitization. Before the reflex can be used as a clinical tool, normative values need to be determined in large scale studies. The aim of this study was to determine the reference values of spinal nociceptive reflexes and subjective pain thresholds (to single and repeated stimulation), and of the area of the reflex receptive fields (RRF) in 300 pain-free volunteers. The influences of gender, age, height, weight, body-mass index (BMI), body side of testing, depression, anxiety, catastrophizing and parameters of Short-Form 36 (SF-36) were analyzed by multiple regressions. The 95% confidence intervals were determined for all the tests as normative values. Age had a statistically and quantitatively significant impact on the subjective pain threshold to single stimuli. The reflex threshold to single stimulus was lower on the dominant compared to the non-dominant side. Depression had a negative impact on the subjective pain threshold to single stimuli. All the other analyses either did not reveal statistical significance or displayed quantitatively insignificant correlations. In conclusion, normative values of parameters related to the spinal nociceptive reflex were determined. This allows their clinical application for assessing central hyperexcitability in individual patients. The parameters investigated explore different aspects of sensitization processes that are largely independent of demographic characteristics, cognitive and affective factors.

Normative data for lung function and exhaled nitric oxide in unsedated healthy infants

Despite association with lung growth and long-term respiratory morbidity, there is a lack of normative lung function data for unsedated infants conforming to latest European Respiratory Society/American Thoracic Society standards. Lung function was measured using an ultrasonic flow meter in 342 unsedated, healthy, term-born infants at a mean ± sd age of 5.1 ± 0.8 weeks during natural sleep according to the latest standards. Tidal breathing flow-volume loops (TBFVL) and exhaled nitric oxide (eNO) measurements were obtained from 100 regular breaths. We aimed for three acceptable measurements for multiple-breath washout and 5-10 acceptable interruption resistance (R(int)) measurements. Acceptable measurements were obtained in ≤ 285 infants with high variability. Mean values were 7.48 mL·kg⁻¹ (95% limits of agreement 4.95-10.0 mL·kg⁻¹) for tidal volume, 14.3 ppb (2.6-26.1 ppb) for eNO, 23.9 mL·kg⁻¹ (16.0-31.8 mL·kg⁻¹) for functional residual capacity, 6.75 (5.63-7.87) for lung clearance index and 3.78 kPa·s·L⁻¹ (1.14-6.42 kPa·s·L⁻¹) for R(int). In males, TBFVL outcomes were associated with anthropometric parameters and in females, with maternal smoking during pregnancy, maternal asthma and Caesarean section. This large normative data set in unsedated infants offers reference values for future research and particularly for studies where sedation may put infants at risk. Furthermore, it highlights the impact of maternal and environmental risk factors on neonatal lung function.

German validation of the Conners Adult ADHD Rating Scales–self-report (CAARS-S) I: Factor structure and normative data

Attention-deficit/hyperactivity disorder (ADHD) often persists into adulthood. Instruments for diagnosing ADHD in childhood are well validated and reliable, but diagnosis of ADHD in adults remains problematic. Attempts have been made to develop criteria specific for adult ADHD, resulting in the development of self-report and observer-rated questionnaires. To date, the Conners Adult ADHD Rating Scales (CAARS) are the international standard for questionnaire assessment of ADHD. The current study evaluates a German version of the CAARS self-report (CAARS-S).

An empirical examination of the integration of causal attribution and social learning theories in achievement situations

Using path analysis, the present investigation sought to clarify possible operational linkages among constructs from social learning and attribution theories within the context of a self-esteem system. Subjects were 300 undergraduate university students who completed a measure of self-esteem and indicated expectancies for success and minimal goal levels for an experimental task. After completing the task and receiving feedback about their performance, subjects completed causal attribution and self-esteem questionnaires. Results revealed gender differences in the degree and strength of the proposed relations, but not in the mean levels of the variables studied. Results suggested that the integration of social learning and attribution theories within a single conceptual model provides a better understanding of students' behaviors and self-esteem in achievement situations.

Interactions between short-term and long-term plasticity: shooting for a moving target

Far from being static transmission units, synapses are highly dynamical elements that change over multiple time scales depending on the history of the neural activity of both the pre- and postsynaptic neuron. Moreover, synaptic changes on different time scales interact: long-term plasticity (LTP) can modify the properties of short-term plasticity (STP) in the same synapse. Most existing theories of synaptic plasticity focus on only one of these time scales (either STP or LTP or late-LTP) and the theoretical principles underlying their interactions are thus largely unknown. Here we develop a normative model of synaptic plasticity that combines both STP and LTP and predicts specific patterns for their interactions. Recently, it has been proposed that STP arranges for the local postsynaptic membrane potential at a synapse to behave as an optimal estimator of the presynaptic membrane potential based on the incoming spikes. Here we generalize this approach by considering an optimal estimator of a non-linear function of the membrane potential and the long-term synaptic efficacy—which itself may be subject to change on a slower time scale. We find that an increase in the long-term synaptic efficacy necessitates changes in the dynamics of STP. More precisely, for a realistic non-linear function to be estimated, our model predicts that after the induction of LTP, causing long-term synaptic efficacy to increase, a depressing synapse should become even more depressing. That is, in a protocol using trains of presynaptic stimuli, as the initial EPSP becomes stronger due to LTP, subsequent EPSPs should become weakened and this weakening should be more pronounced with LTP. This form of redistribution of synaptic efficacies agrees well with electrophysiological data on synapses connecting layer 5 pyramidal neurons.

dGEMRIC and subsequent T1 mapping of the hip at 1.5 Tesla: normative data on zonal and radial distribution in asymptomatic volunteers

To characterize the zonal distribution of three-dimensional (3D) T1 mapping in the hip joint of asymptomatic adult volunteers.

Plato and Frankfurt: Two Theories of the Relations Between Love and Living Well

This thesis provides a comparison of the ideas of caring and love as they appear in the works of Plato and Frankfurt. Frankfurt, a contemporary philosopher, maintains that an individual arrives at the most meaningful life through understanding what it is that heor she cares about the most. Interestingly, the instances of eros in Plato's Symposium and Phaedrus resonate with this idea. We see throughout these erotic dialogues similarities to Frankfurt's notions of care and love.Throughout his many works, Frankfurt provides us with several distinct features of care and love. This thesis offers an in depth discussion of each of these features andalso provides commentary from other contemporary philosophers who are familiar with Frankfurt's work. In addition, this thesis applies these features of care and love to Plato's erotic dialogues, and emphasizes areas in which Plato and Frankfurt agree and those inwhich they disagree. In essence, it becomes apparent that while there are many similarities between the ideas of these two prominent thinkers, Plato and Frankfurt do not agree about what constitutes the best human life. Plato maintains that the best life is onespent dedicated to philosophy and in pursuit of the 'good'. Frankfurt, on the other hand,imposes no such limitations on what we should consider the best life because people are likely to have different life experiences that lead them to care about and love different things. Instead he suggests that the best or most meaningful human life is one in which a person spends his or her life caring about the things he or she does, indeed, care aboutand loving those things he or she does, indeed, love.

Can the neuroeconomics revolution revolutionize psychiatry?

Neuroeconomics is a rapidly growing new research discipline aimed at describing the neural substrate of decision-making using incentivized decisions introduced in experimental economics. The novel combination of economic decision theory and neuroscience has the potential to better examine the interactions of social, psychological and neural factors with regard to motivational forces that may underlie psychiatric problems. Game theory will provide psychiatry with computationally principled measures of cognitive dysfunction. Given the relatively high heritability of these measures, they may contribute to improving phenotypic definitions of psychiatric conditions. The game-theoretical concepts of optimal behavior will allow description of psychopathology as deviation from optimal functioning. Neuroeconomists have successfully used normative or near-normative models to interpret the function of neurotransmitters; these models have the potential to significantly improve neurotransmitter theories of psychiatric disorders. This paper will review recent evidence from neuroeconomics and psychiatry in support of applying economic concepts such as risk/uncertainty preference, time preference and social preference to psychiatric research to improve diagnostic classification, prevention and therapy.