A sensory-labeled line for cold: TRPM8-expressing sensory neurons define the cellular basis for cold, cold pain, and cooling-mediated analgesia.

Many primary sensory neurons are polymodal, responding to multiple stimulus modalities (chemical, thermal, or mechanical), yet each modality is recognized differently. Although polymodality implies that stimulus encoding occurs in higher centers, such as the spinal cord or brain, recent sensory neuron ablation studies find that behavioral responses to different modalities require distinct subpopulations, suggesting the existence of modality-specific labeled lines at the level of the sensory afferent. Here we provide evidence that neurons expressing TRPM8, a cold- and menthol-gated channel required for normal cold responses in mammals, represents a labeled line solely for cold sensation.

A portable system for recording neural activity in indoor and outdoor environments.

We present a self-contained portable USB based device that can amplify and record small bioelectric signals from insects and animals. The system combines a purpose built low noise amplifier with off the shelf components to provide a low cost low power system for recording electrophysiological signals. Using open source software the system is programmed as a simple USB device and can be connected to any USB capable computer for recording data.

Mechanisms of top-down attention.

Attention exhibits characteristic neural signatures in brain regions that process sensory signals. An important area of future research is to understand the nature of top-down signals that facilitate attentional guidance towards behaviorally relevant locations and features. In this review, we discuss recent studies that have made progress towards understanding: (i) the brain structures and circuits involved in attentional allocation; (ii) top-down attention pathways, particularly as elucidated by microstimulation and lesion studies; (iii) top-down modulatory influences involving subcortical structures and reward systems; (iv) plausible substrates and embodiments of top-down signals; and (v) information processing and theoretical constraints that might be helpful in guiding future experiments.

Training top-down attention improves performance on a triple-conjunction search task.

Training has been shown to improve perceptual performance on limited sets of stimuli. However, whether training can generally improve top-down biasing of visual search in a target-nonspecific manner remains unknown. We trained subjects over ten days on a visual search task, challenging them with a novel target (top-down goal) on every trial, while bottom-up uncertainty (distribution of distractors) remained constant.