Enhanced neuronal excitability in rat CA1 pyramidal neurons following trace eyeblink conditioning acquisition is not due to alterations in I M

Previous work done by our laboratory has demonstrated a reduction of the post-burst afterhyperpolarization (AHP) and accommodation following trace eyeblink conditioning in rabbit CA1 pyramidal neurons. Our laboratory has also demonstrated a reduction in the AHP in rat CA1 pyramidal neurons following spatial learning. In the current study we have extended our findings in rabbits by showing a reduction in both the AHP and accommodation in F344 X BN rat CA1 pyramidal neurons following acquisition of trace eyeblink conditioning. A component current of the AHP, I(M), was evaluated with a specific blocker of this current, and showed no apparent contribution to the learning-related increase in neuronal excitability. Rather, a reduction in an isoproterenol-sensitive component of the AHP, presumably sI(AHP), was observed to underlie the learning-specific change.     

Socialized reflexivity and self‐exertion: Mandala Model of Self and its role in mental health

The Mandala Model of Self (MMS) refers to the well‐functioning self leading to ultimate happiness in various cultures. This research provides the first empirical examination of the role of MMS in mental health in Confucian societies. The MMS Scale (MMSS) was developed, and its psychometric properties are described. A correlational study demonstrated that the MMSS, along with its two factors—socialized reflexivity and self‐exertion—validly measures certain mental health constructs. A quasi‐experimental study reliably distinguished persons engaged in the cultivation of the Mandala self from those who had not. Finally, a study with adolescents demonstrated that the scores of the MMSS are a better predictor of resilience than is extroversion or neuroticism. The present research provides empirical support for the theory underlying the MMS and its key contribution to mental health.     

A study of Internet addiction through the lens of the interpersonal theory.

Previous studies have presented conflicting claims regarding reasons that people become addicted to the Internet. In this study, we attempted to identify predictors of Internet addiction based on Sullivan's interpersonal theory and Internet addiction literature. In our research model, it is hypothesized that good parent-child relationship positively correlates with good interpersonal relationships, which in turn are hypothesized to correlate with undesirable social anxiety. In addition, both parent-child and interpersonal relationships are hypothesized to negatively correlate with Internet addiction, whereas the level of social anxiety is hypothesized to positively correlate with Internet addiction. The results of this study confirm the research model hypotheses, indicating that the quality of parent-child relationship is indeed positively correlated to the quality of our participants' interpersonal relationships and that frustrating interpersonal relationships may raise the level of social anxiety. In addition, interpersonal relationships, the parent-child relationship, and social anxiety all influence Internet addiction, as predicted by the model. Finally, the more social anxiety and discontent with their peer interactions the participants experienced, the more addicted they were to the Internet.     

The six determinants of gait and the inverted pendulum analogy: A dynamic walking perspective

We examine two prevailing, yet surprisingly contradictory, theories of human walking. The six determinants of gait are kinematic features of gait proposed to minimize the energetic cost of locomotion by reducing the vertical displacement of the body center of mass (COM). The inverted pendulum analogy proposes that it is beneficial for the stance leg to behave like a pendulum, prescribing a more circular arc, rather than a horizontal path, for the COM. Recent literature presents evidence against the six determinants theory, and a simple mathematical analysis shows that a flattened COM trajectory in fact increases muscle work and force requirements. A similar analysis shows that the inverted pendulum fares better, but paradoxically predicts no work or force requirements. The paradox may be resolved through the dynamic walking approach, which refers to periodic gaits produced almost entirely by the dynamics of the limbs alone. Demonstrations include passive dynamic walking machines that descend a gentle slope, and active dynamic walking robots that walk on level ground. Dynamic walking takes advantage of the inverted pendulum mechanism, but requires mechanical work to transition from one pendular stance leg to the next. We show how the step-to-step transition is an unavoidable energetic consequence of the inverted pendulum gait, and gives rise to predictions that are experimentally testable on humans and machines. The dynamic walking approach provides a new perspective, focusing on mechanical work rather than the kinematics or forces of gait. It is helpful for explaining human gait features in a constructive rather than interpretive manner.     

Comparison of kinematic and kinetic methods for computing the vertical motion of the body center of mass during walking

The vertical excursion of the body center of mass (BCOM) was calculated using three different techniques commonly used by motion analysis laboratories. The sacral marker method involved estimating vertical BCOM motion by tracking the position of a reflective marker that was placed on the sacrum of subjects as they walked. The body segmental analysis technique determined the vertical motion of the BCOM from a weighted average of the vertical positions of the centers of mass of individual body segments for each frame of kinematic data acquired during the data trial. Anthropomorphic data from standard tables were used to determine the mass fractions and the locations of the centers of mass of each body segment. The third technique involved calculating BCOM vertical motion through double integration of force platform data. Data was acquired from 10 able-bodied, adult research subjects--5 males and 5 females--walking at speeds of 0.8, 1.2, 1.6, and 2.0 m/s. A repeated measures ANOVA indicated that at the slowest walking speed the vertical excursions calculated by all three techniques were similar, but at faster speeds the sacral marker significantly (p < 0.001) overestimated the vertical excursion of the BCOM compared with the other two methods. The body segmental analysis and force platform techniques were in agreement at all walking speeds. Discrepancies between the sacral marker method and the other two techniques were explained using a simple model; the reciprocal configuration of the legs during double support phase significantly raises the position of the BCOM within the trunk at longer step lengths, corresponding to faster walking speeds. The sacral marker method may provide a reasonable approximation of vertical BCOM motion at slow and freely selected speeds of able-bodied walking. However, the body segmental analysis or force platform techniques will probably yield better estimates at faster walking speeds or in persons with gait pathologies.     

A Developmental Perspective of Marriage and Family Therapist's Ethical Principles: Support for the Practitioner–Ethics Relationship Model

This study explored therapists' professional ethics by assessing therapist at-risk behaviors as they relate to ethical proficiency in the field of Marriage and Family Therapy. A survey assessing practice behaviors was distributed among marriage and family therapists (MFTs) of varying levels of experience. Data gathered were analyzed using factor analysis, structural equation modeling, and multiple regression. Results indicate a positive relationship between the latent variables of risk and justification, as well as a significant relationship between these variables and years of clinical experience. Findings provide evidence to support the practitioner–ethics relationship model proposed by the authors. Implications of these findings, as well as future directions for research and policy are suggested.     

Simultaneous training on two hippocampus-dependent tasks facilitates acquisition of trace eyeblink conditioning

A common cellular alteration, reduced post-burst afterhyperpolarization (AHP) in CA1 neurons, is associated with acquisition of the hippocampus-dependent tasks trace eyeblink conditioning and the Morris water maze. As a similar increase in excitability is correlated with these two learning paradigms, we sought to determine the interactive behavioral effects of training animals on both tasks by using either a consecutive or simultaneous training design. In the consecutive design, animals were trained first on either the trace eyeblink conditioning task for six sessions, followed by training on the water maze task for six sessions, or vice versa. The simultaneous design consisted of six or 11 training days; animals received one session/day of both trace eyeblink conditioning and water maze training. Separate groups were used for consecutive and simultaneous training. Animals trained on both tasks simultaneously were significantly facilitated in their ability to acquire the trace eyeblink conditioning task; no effect of simultaneous training was seen on the water maze task. No effect was seen on acquisition for either task when using the consecutive training design. Taken together, these findings provide insight into how the hippocampus processes information when animals learn multiple hippocampus-dependent tasks.     

Using the short mood and feelings questionnaire to detect depression in detained adolescents

The Mood and Feelings Questionnaire (MFQ) is examined for its utility in screening youth in juvenile justice settings for depression. In a cross-sectional study conducted at King County Juvenile Detention Center, a representative sample of 228 detained adolescents complete structured assessments, including the MFQ and the Massachusetts Youth Screening Instrument. Fifty youth also complete the Voice-Diagnostic Interview Schedule for Children. Internal reliability coefficient for the MFQ short form (SMFQ) is = .87. Factor analysis produces a unifactorial scale with item loadings of .43 to .78. At SMFQ cutoff > or = 10, sensitivity and specificity are optimized at 1.00/0.79. Prevalence of major depressive disorder is estimated at 32.1% (95% Confidence Interval = 25.3% to 39.2%). The SMFQ shows potential for depression screening of detained adolescents.