Operant conditioning is a common tool for studying cognitive aspects of brain functions. As the first step toward understanding those functions in simple invertebrate microbrains, we tested whether operant conditioning could be applied to train American lobster Homarus americanus that has been extensively adopted as an animal model for neurophysiological analyses of nervous system functions and...

Effective treatments for chronic pain have been based on the operant model for chronic pain, which holds that pain behaviours can be operantly controlled by various reinforcers. Support for the operant model comes primarily from treatment/outcome studies which report significant reductions in pain behaviours in chronic pain patients, but fail to demonstrate the underlying operant thesis that va...

Operant (instrumental) and classical (Pavlovian) conditioning are taught as the simplest forms of associative learning. Recent research in several invertebrate model systems has now accumulated evidence that the dichotomy is not as simple as it seemed. During operant learning in the fruit fly Drosophila, at least two genetically distinct learning systems interact dynamically. Inspired by analog...

Macaca nemestrina monkeys received unilateral interruption of the spinothalamic tract, producing contralateral hypalgesia and a bilateral decrease in amplitude of the flexion reflex. These effects on operant escape and reflex responses to electrocutaneous stimulation (ES) were monitored for months to evaluate relationships between the extent of each lesion and the presence or absence of recover...

I present an Hipparcos color-magnitude diagram (CMD) that is color-coded by transverse velocity v ⊥. This illustrates the connection between the photomet-ric and kinematic properties of various stellar populations in a manner that is particularly suitable to introductory astronomy courses.

Measuring the quality of metadata is only possible by assessing the quality of the underlying schema and the metadata instance. We propose some factors that are measurable automatically for metadata according to the CMD framework, taking into account the variability of schemas that can be defined in this framework. The factors include among others the number of elements, the (re-)use of reusabl...