Conditioned inhibition of cocaine seeking in rats

Despite its potential relevance to the treatment of drug abuse, conditioned inhibition of drug seeking has not been systematically investigated before. In this study, rats could self-administer cocaine by lever pressing whenever a click or tone was present. Responding was not reinforced when a light was present. The light was presented simultaneously with the click (i.e., in an excitatory context) in 1 group, but the light was always presented alone in another group. When it was later presented in compound with the tone, the light was a highly effective conditioned inhibitor, suppressing cocaine seeking by 92% in the former group and by 74% in the latter. These results suggest ways to improve cue-oriented behavioral treatments for drug abuse.     

The production and perception of long calls by cotton-top tamarins (Saguinus oedipus): acoustic analyses and playback experiments

The authors' goal was to provide a better understanding of the relationship between vocal production and perception in nonhuman primate communication. To this end, the authors examined the cotton-top tamarin's (Saguinus oedipus) combination long call (CLC). In Part 1 of this study, the authors carried out a series of acoustic analyses designed to determine the kind of information potentially encoded in the tamarin's CLC. Using factorial analyses of variance and multiple discriminant analyses, the authors explored whether the CLC encodes 3 types of identity information: individual, sex, and social group. Results revealed that exemplars could be reliably assigned to these 3 functional classes on the basis of a suite of spectrotemporal features. In Part 2 of this study, the authors used a series of habituation-dishabituation playback experiments to test whether tamarins attend to the encoded information about individual identity. The authors 1st tested for individual discrimination when tamarins were habituated to a series of calls from 1 tamarin and then played back a test call from a novel tamarin; both opposite- and same-sex pairings were tested. Results showed that tamarins dishabituated when caller identity changed but transferred habituation when caller identity was held constant and a new exemplar was played (control condition). Follow-up playback experiments revealed an asymmetry between the authors' acoustic analyses of individual identity and the tamarins' capacity to discriminate among vocal signatures; whereas all colony members have distinctive vocal signatures, we found that not all tamarins were equally discriminable based on the habituation-dishabituation paradigm.     

Impaired visual perception of hurtful actions in patients with chronic low back pain

Visually presented biological motion stimuli activate regions in the brain that are also related to musculo-skeletal pain. We therefore hypothesized that chronic pain impairs the perception of visually presented actions that involve body parts that hurt. In the first experiment, chronic back pain (CLBP) patients and healthy controls judged the lifted weight from point-light biological motion displays. An actor either lifted an invisible container (5, 10, or 15 kg) from the floor, or lifted and manipulated it from the right to the left. The latter involved twisting of the lower back and would be very painful for CLBP patients. All participants recognized the displayed actions, but CLBP patients were impaired in judging the difference in handled weights, especially for the trunk rotation. The second experiment involved discrimination between forward and backward walking. Here the patients were just as good as the controls, showing that the main result of the first experiment was indeed specific to the sensory aspects of the task, and not to general impairments or attentional deficits. The results thus indicate that the judgment of sensorimotor aspects of a visually displayed movement is specifically affected by chronic low back pain.     

Brain activity for visual judgment of lifted weight

It is well established that humans can recognize high-level aspects from point-light biological motion, such as gender and mood. If the task is to judge the manipulated weight we expected that sensorimotor regions should be recruited in the brain. Moreover, we have recently shown that chronic pain in a limb that is involved in the presented movement disturbs the weight judgment. We therefore hypothesized that some cortical regions usually activated during the processing of pain will also be activated while viewing point-light biological motion with the instruction to judge the manipulated weights. We investigated point-light biological motion of two types of movements performed with different weights in a blocked fMRI experiment in healthy subjects. In line with our a priori hypothesis, we found strong activity in the regions known as the neuromatrix of pain, such as the anterior cingulate (ACC), insula, as well as primary and secondary somatosensory regions. We also found activation in the occipital and temporal regions that are typical for biological motion, as well as regions in the cerebellum and prefrontal cortex. The activation of the somatosensory regions probably serves the judgment of the biological motion stimuli. Activation of the anterior cingulate and the insula might be explained by their role in the integration of behaviorally relevant information. Alternatively, these structures are known to be involved in the processing of nociceptive information and pain. So it seems possible that the interference between judgment of weights and perception of pain in chronic pain patients occurs in the somatosensory areas, anterior cingulate and/or insula. This finding provides important information as to the underlying mechanisms used for the weight judgment task, but also why chronic pain interferes with this task.     

The marital status inventory: Development of a measure of dissolution potential

Abstract

The development of a 14-item intensity scale measuring likelihood of marriage dissolution is described. The Marital Status Inventory (MSI) forms a Guttman-like scale. Preliminary discriminant validity data are presented for the self-report scale indicating that couples presenting with marital problems score significantly higher than couples seeking parent-child related therapy. The predictive validity of the scale remains to be demonstrated, but the MSI is reported for use by researchers and clinicians.     

Ethics and Culture in Mental Health Care

This article examines the complex relationship between culture, values, and ethics in mental health care. Cultural competence is a practical, concrete demonstration of the ethical principles of respect for persons, beneficence (doing good), nonmaleficence (not doing harm), and justice (treating people fairly)—the cornerstones of modern ethical codes for the health professions. Five clinical cases are presented to illustrate the range of ethical issues faced by mental health clinicians working in a multicultural environment, including issues of therapeutic boundaries, diagnosis, treatment choice, confidentiality and informed consent, and the just distribution of limited health care resources.