Neuroscience and biobehavioral reviews
-
Decades of pain research have succeeded in elucidating complex mechanisms of acute activation and chronic sensitization of nociceptors leading to pain. In contrast, itch conditions have received less attention and even basic mechanisms for the induction of itch are still unclear. In this review we describe itch-specific pathways, but also evidence for a modified pattern theory of pruritus offering independent mechanisms for the itch induction. ⋯ However, concerning mechanisms of sensitization to itch or pain, surprisingly similar patterns have been observed lately in both inflamed tissue and in the spinal cord. These similarities open up two highly interesting perspectives: the role of well established analgesic therapeutic concepts can be validated in chronic itch conditions and on the other hand investigations of sensitization in easily accessible pruritic skin may help to validate concepts of nociception in humans. These perspectives illustrate that itch and pain research no longer follows separate paths, but can be advantageously interconnected.
-
Neurosci Biobehav Rev · Feb 2010
ReviewKeeping pain in mind: a motivational account of attention to pain.
Attention is a key concept in many theories of pain perception. A clinically popular idea is that pain is more intense in persons who are hypervigilant for or bias their attention to pain information. So far, evidence for such bias in pain patients as compared to healthy persons is inconclusive. ⋯ Attentional processing of pain information will be particularly enhanced when the focal goal is related to pain management (e.g., attempting to gain control). Future research should systematically investigate the role of motivation and goal pursuit in the attentional processing of pain-related information. This motivational perspective offers a powerful framework to explain inter- and intra-individual differences in the deployment of attention to pain-related information.
-
Neurosci Biobehav Rev · Jan 2010
ReviewA critical review of human endotoxin administration as an experimental paradigm of depression.
The syndrome called depression may represent the common final pathway at which different aetiopathogenic processes converge. One such aetiopathogenic process is innate immune system activation. Some depressed patients have increased levels of inflammatory cytokines and other immunologic abnormalities. ⋯ A new approach to depression research would be to use immune stimuli to elicit depressive symptoms in humans. Here we review each of the symptoms elicited in humans by endotoxin administration, and compare this model to two other immune depression paradigms: interferon-alpha treatment and typhoid vaccine administration, to assess to what degree endotoxin administration represents a valid model of immune depression. We also review corresponding behavioral changes in rodents and the potential molecular pathways through which immune system activation produces each symptom.
-
Neurosci Biobehav Rev · Jul 2009
ReviewDeep brain stimulation, vagal nerve stimulation and transcranial stimulation: An overview of stimulation parameters and neurotransmitter release.
Neurological disorders are among the most challenging medical problems faced by science today. To treat these disorders more effectively, new technologies are being developed by reviving old ideas such as brain stimulation. This review aims to compile stimulation techniques that are currently in use to explore or treat neurological disorders. ⋯ Scientific and clinical applications have largely preceded the development of extensive animal models, presenting a challenge for researchers. This has left researchers with information on alleviating symptoms in humans but without solid research as to the mechanisms and neurobiological effects of the devices. This review combines stimulation parameters developed in animal models and stimulation techniques used in human treatment; thus, resulting in a greater understanding of the mechanisms and neurobiological effects of neuromodulation devices.
-
Neurosci Biobehav Rev · Jun 2009
ReviewStress-induced prefrontal reorganization and executive dysfunction in rodents.
The prefrontal cortex (PFC) mediates a range of higher order 'executive functions' that subserve the selection and processing of information in such a way that behavior can be planned, controlled and directed according to shifting environmental demands. Impairment of executive functions typifies many forms of psychopathology, including schizophrenia, mood and anxiety disorders and addiction, that are often associated with a history of trauma and stress. ⋯ In parallel, there is growing evidence that stress-induced alterations in PFC neuronal morphology are associated with deficits in rodent executive functions such as working memory, attentional set-shifting and cognitive flexibility, as well as emotional dysregulation in the form of impaired fear extinction. Although the molecular basis of stress-induced changes in PFC morphology and function are only now being elucidated, an understanding of these mechanisms could provide important insight into the pathophysiology of executive dysfunction in neuropsychiatric disease and foster improved strategies for treatment.