Automated gait analysis in the open-field test for laboratory mice

In this article, an automated and accurate mouse observation method, based on a conventional test for motor function evaluation, is outlined. The proposed measurement technique was integrated in a regular open-field test, where the trajectory and locomotion of a free-moving mouse were measured simultaneously. The system setup consisted of a transparent cage and a camera placed below it with its lens pointing upward, allowing for images to be captured from underneath the cage while the mouse was walking on the transparent cage floor. Thus, additional information was obtained about the position of the limbs of the mice for gait reconstruction. In a first step, the camera was calibrated as soon as it was fixed in place. A linear calibration factor, relating distances in image coordinates to real-world dimensions, was determined. In a second step, the mouse was located and its body contour segmented from the image by subtracting a previously taken “background” image of the empty cage from the camera image. In a third step, the movement of the mouse was analyzed and its speed estimated from its location in the past few images. If the speed was above a 1-sec threshold, the mouse was recognized to be running, and the image was further processed for footprint recognition. In a fourth step, color filtering was applied within the recovered mouse region to measure the position of the mouse’s paws, which were visible in the image as small pink spots. Paws that were detected at the same location in a number of subsequent images were kept as footprints—that is, paws in contact with the cage floor. The footprints were classified by their position relative to the mouse’s outline as corresponding to the front left or right paw or the hind left or right paw. Finally, eight parameters were calculated from the footprint pattern to describe the locomotion of the mouse: right/left overlap, front/hind base, right/left front limb stride, and right/left hind limb stride. As an application, the system was tested using normal mice and mice displaying pentobarbital-induced ataxia. The footprint parameters measured using the proposed system showed differences of 10% to 20% between normal and ataxic mice.     

Validity of three measures of communication for predicting relationship adjustment and stability among a sample of young couples

The goal of this study was to examine whether data from 3 different measures of communication (i.e., self-report, quasi-observational, and observational) can predict relationship adjustment and stability 1 year later when used conjointly in a sample of 62 young couples. The 3 measures of communication were the Communication Skills Test--Revised (CST-R), the Communication Box (CB), and the Demand/Withdraw Pattern Questionnaire (DWPQ). Through hierarchical multiple regression analyses, results revealed that the CST-R and the DWPQ predict both genders' relationship adjustment 1 year later when used conjointly. Logistic regression analyses revealed that none of the measures of communication significantly predicted relationship stability. In conclusion, the combination of the CST-R and the DWPQ appears to be useful for longitudinally predicting relationship adjustment.     

Motor fluency deficits in the sequencing of actions in schizophrenia

Many everyday activities depend on the capacity to organize and smoothly execute motor sequences. The authors tested the hypothesis that a sequencing deficit is associated with schizophrenia. They used a new method to distinguish between lower and higher order mechanisms for the impairment. The 1st task involved triggered sequences in which sensory information from 1 movement was the cue for initiation of the following movement. Results showed that the motor sequences were performed as fluently in patients as in controls. The 2nd and 3rd tasks involved sequences in which the entire movement sequence could be preplanned. Patients executed the sequences less fluently than controls but only under the condition where action sequences were required. Furthermore, the patients' fluency deficit increased with sequence complexity. The high discrimination power of Task 3 gave the authors a means to control for a potential psychometric confound involving differential discriminating power and to argue in favor of a specific higher order motor fluency deficit in patients with schizophrenia. It is suggested that basic lower order mechanisms that integrate sensory information with outgoing motor commands are preserved in schizophrenia, whereas higher order integrative mechanisms that are required for the smooth coordination of motor sequences are impaired.     

Impaired strategic regulation of contents of conscious awareness in schizophrenia

Conscious awareness comprises two distinct states, autonoetic and noetic awareness. Schizophrenia impairs autonoetic, but not noetic, awareness. We investigated the strategic regulation of relevant and irrelevant contents of conscious awareness in schizophrenia using a directed forgetting paradigm. Twenty-one patients with schizophrenia and 21 normal controls were presented with words and told to learn some of them and forget others. In a subsequent test, they were asked to recognize all the words they had seen previously and give remember, know or guess responses according to whether they recognized words on the basis of autonoetic awareness, noetic awareness, or guessing. Overall, patients showed the same degree of a directed forgetting effect as normal subjects. However, whereas the effect was observed both for remember and know responses in normal subjects, it was observed for know, but not for remember, responses in patients. These results indicate that patients with schizophrenia exhibit an impaired strategic regulation of contents of autonetic awareness for relevant and irrelevant information.     

Self-images and related autobiographical memories in schizophrenia

Schizophrenia is a severe mental illness, which affects sense of identity. While the ability to have a coherent vision of the self (i.e., self-images) relies partly on its reciprocal relationships with autobiographical memories, little is known about how memories ground "self-images" in schizophrenia. Twenty-five patients with schizophrenia and 25 controls were asked to give six autobiographical memories related to four self-statements they considered essential for defining their identity. Results showed that patients' self-images were more passive than those of controls. Autobiographical memories underlying self-images were less thematically linked to these self-images in patients. We also found evidence of a weakened sense of self and a deficient organization of autobiographical memories grounding the self in schizophrenia. These abnormalities may account for the poor cohesiveness of the self in schizophrenia.     

Feasibility and impact of a school-based intervention for families of urban adolescents with asthma: results from a randomized pilot trial

The purpose of this study was to test the feasibility and short-term outcomes of Asthma: It's a Family Affair!, a school-based intervention for adolescents with asthma and their caregivers. Twenty-four ethnic minority families with a middle school student with asthma were randomized to immediate intervention or no-treatment control. Intervention students received six group sessions on prevention and management of asthma. Caregivers received five group sessions teaching child-rearing skills to support the youth's autonomy and asthma self-management. All students attended all sessions; caregivers attended an average of three. Two months post-intervention, relative to controls, intervention caregivers reported better problem-solving with children. Intervention students were more responsible for carrying medication, took more prevention steps, and woke fewer nights from asthma. The intervention resulted in positive short-term changes in family relations, asthma management by students, and health status.     

Backward and forward masking in the perception of cutaneous stimuli

Masking of the perception of an electrical test stimulus by a mechanical shock was studied in six Ss. Forward and backward masking were observed in all Ss, the former being of longer duration. Duration of the masking effects is inversely related to the intensity of the test stimulus. Masking effects may be preceded and followed by perceptual facilitation. The masking effects may be responsible for the alterations in the perception of a somaesthetic stimulus before and during movement of the stimulated area.