New lessons from knockout mice: The role of serotonin during development and its possible contribution to the origins of neuropsychiatric disorders

Serotonin (5-HT) modulates numerous processes in the central nervous system that are relevant to neuropsychiatric function and dysfunction. It exerts significant effects on anxiety, mood, impulsivity, sleep, ingestive behavior, reward systems, and psychosis. Serotonergic dysfunction has been implicated in several psychiatric conditions but efforts to more clearly understand the mechanisms of this influence have been hampered by the complexity of this system at the receptor level. There are at least 14 distinct receptors that mediate the effects of 5-HT as well as several enzymes that control its synthesis and metabolism. Pharmacologic agents that target specific receptors have provided clues regarding the function of these receptors in the human brain. 5-HT is also an important modulator of neural development and several groups have employed a genetic strategy relevant to behavior. Several inactivation mutations of specific 5-HT receptors have been generated producing interesting behavioral phenotypes related to anxiety, depression, drug abuse, psychosis, and cognition. In many cases, knockout mice have been used to confirm what has already been suspected based on pharmacologic studies. In other instances, mutations have demonstrated new functions of serotonergic genes in development and behavior.     

Lesion of the ventral periaqueductal gray reduces conditioned fear but does not change freezing induced by stimulation of the dorsal periaqueductal gray

Previously-reported evidence showed that freezing to a context previously associated with footshock is impaired by lesion of the ventral periaqueductal gray (vPAG). It has also been shown that stepwise increase in the intensity of the electrical stimulation of the dorsal periaqueductal gray (dPAG) produces alertness, then freezing, and finally escape. These aversive responses are mimicked by microinjections of GABA receptor antagonists, such as bicuculline, or blockers of the glutamic acid decarboxylase (GAD), such as semicarbazide, into the dPAG. In this work, we examined whether the expression of these defensive responses could be the result of activation of ventral portion of the periaqueductal gray. Sham- or vPAG electrolytic–lesioned rats were implanted with an electrode in the dPAG for the determination of the thresholds of freezing and escape responses. The vPAG electrolytic lesions were behaviorally verified through a context-conditioned fear paradigm. Results indicated that lesion of the vPAG disrupted conditioned freezing response to contextual cues associated with footshocks but did not change the dPAG electrical stimulation for freezing and escape responses. In a second experiment, lesion of the vPAG also did not change the amount of freezing and escape behavior produced by microinjections of semicarbazide into the dPAG. These findings indicate that freezing and escape defensive responses induced by dPAG stimulation do not depend on the integrity of the vPAG. A discussion on different neural circuitries that might underlie different inhibitory and active defensive behavioral patterns that animals display during threatening situations is presented.     

Is Therapeutic Alliance Influenced by a Feminist Approach to Therapy?

Although the feminist critique of marriage and family therapy has been a significant part of the literature for many years, its impact has been blunted by two criticisms. The first suggests that the feminist critique lacks empirical support. The second suggests that the feminist critique promotes an alliance with women clients at the expense of men. The first criticism has been addressed in recent years. The present study examined the relationship between feminist principles and therapeutic alliance. Results suggest that feminist principles actually enhance therapeutic relationship for men clients but has no effect on therapeutic relationship for women clients.of the Marriage and Family Therapy Program     

The Effect of Inhibition of Return on Lexical Access

Abstract—Inhibition of return refers to a bias against returning attention to a location or object that has been recently attended. Recent research has shown that inhibition of return can be found not only in simple detection tasks, but also in tasks requiring relatively simple discrimination judgments. The present experiments examined whether inhibition of return occurs in tasks that require complex discriminations such as lexical decision and categorization tasks. Not only was inhibition of return found in both experiments, but a greater amount of inhibition was found for low-frequency words than for high-frequency words. These findings suggest that inhibition of return not only inhibits returning attention to previously attended locations, but can also affect the processing that is required for lexical access.     

Research misconduct—Have we reached the turning point at last?

The laissez-faire attitude towards dishonesty in research has simply created an environment for widespread escalation of the problem. Can we now believe anything we read? Why should we have confidence in an author because of his eminence? Should we automatically accept that clinical trials are always conducted with total integrity? Why have we been afraid to tackle this crisis head-on?     

Domestic Abuse as Terrorism

A number of philosophers and feminist authors have recently equated domestic abuse with the ubiquitous and ill‐defined concept of “terrorism.” Claudia Card, for instance, argues that domestic abuse is a frequently ignored form of terrorism that creates and maintains “heterosexual male dominance and female dependence and service” (Card 2003). Alison Jaggar, in a recent article, also concludes that an acceptable definition of terrorism will find rape and domestic violence to be terrorist acts (Jaggar 2005). Yet there seem to be several obstacles to any simple appropriation of the term “terrorism” for cases of domestic abuse. In this paper I will address what I take to be three significant problems that might be raised with regard to any attempt to identify domestic abuse as an act of terrorism. These problems include the fact that a) definitions of terrorism usually require clear political motivations, b) definitions of terrorism normally require that the terrorist intend to create a climate of terror, and c) adopting the term terrorism for cases of domestic abuse might appear simply inappropriate or unhelpful. I will argue, however, that each of these possible objections can be answered effectively and that domestic abuse rightly falls under the rubric of terrorism.     

Examination of Negative Peer Contagion in a Residential Care Setting

There has been ongoing concern about the negative impact of residential treatment on youth in care. Research examining the impact of negative peer influence in juvenile justice, education, and residential care settings is reviewed. A study was conducted to examine the impact of negative peer contagion on the level of problem behavior in a residential care program, and the extent to which caregiver experience and youth time-in-program mediated that relationship. The study used archival data for 1,438 first-time admissions to a large Midwestern out-of-home residential program for youth with emotional and behavioral problems. Hierarchical Linear Modeling was used to examine the relationship between daily reports of conduct and oppositional defiant disorder (CD/ODD) behaviors and the percentage of conduct disorder youth living in a home. Greater exposure to conduct disordered peers was not related to increased rates of CD/ODD behavior. CD/ODD behavior was directly related to direct care staff level of experience and youth time in program. Implications for residential care are discussed.     

Examining the relationship between family context and children’s physical activity beliefs: The role of parenting style

Objectives

Previous research studies examining parental influences on children’s physical activity (PA) have focused primarily on parents’ own PA behavior, as well as their PA-related beliefs and socially supportive behaviors. The present study, although aligned with this mainstream parental influence research, was grounded in a broader child development perspective to examine the influence of parenting style on children’s PA beliefs and quality of parent-child communication.

Method

Self-report questionnaires were administered to 173 children ranging in age from 9 to 12 years to assess their perceptions of parenting style, parent-child communication patterns, as well as their own perceptions of fitness competence, value, and goal orientation.

Results

Children’s constellation of beliefs and attitudes regarding PA as well as their perceptions of the parent-child communication process did vary as a function of the type of parenting style they perceived their parents to use. High challenge parenting style was linked to higher perceived fitness competence and value on the part of the children. High support parenting style was linked to more positive perceived parent-child communication patterns.

Conclusion

Parenting style may be a critical underlying family process variable that impacts children’s development of a positive constellation of beliefs about PA. Future work is needed to link parenting style and children’s PA beliefs to their PA behavior.     

The Argument from Skepticism for Contextualism

Epistemic contextualism was originally motivated and supported by the response it provides to skeptical paradox. Although there has been much discussion of the contextualist response to skeptical paradox, not much attention has been paid to the argument from skepticism for contextualism. Contextualists argue that contextualism accounts for the plausibility and apparent inconsistency of a set of paradoxical claims better than any classical invariantist theory. In this paper I focus on and carefully examine the argument from skepticism for contextualism. I argue not only that the prima facie advantage of contextualism is specious, but also that contextualism is in fact at a competitive disadvantage with respect to two classical invariantist views. I also argue that contextualism takes an arbitrary and unsatisfying strategy in its response to skepticism. That contextualism is alone in taking this arbitrary strategy marks a second competitive disadvantage for it. In addition, I argue that the contextualist response to skeptical paradox regenerates a skeptical paradox which contextualism is powerless to solve. Consequently, the argument from skepticism for contextualism fails. Furthermore, this feature of the contextualist response to skeptical paradox completely undermines the motivation and support for contextualism deriving from its treatment of skeptical paradox. I conclude that the argument from skepticism for contextualism fails, and that the contextualist response to skeptical paradox fails to motivate contextualism, pending the success of another argument for the contextualist thesis.