Effects of ratio contingencies on responding maintained by schedules of electric-shock presentation (response-produced shock)

Squirrel monkeys' lever pressing was established under fixed-interval schedules of electric-shock presentation (response-produced shock). After appropriate temporal patterns of lever pressing were engendered, either fixed-ratio schedules of shock presentation were added to the fixed interval, or yoked variable-ratio schedules were substituted for the fixed-interval schedules. When fixed-ratio schedules were added, there was an initial rise in response rate and schedule-appropriate patterns of responding developed. After many sessions, however, responding ceased abruptly, in some cases with remarkable quickness. When variable-ratio schedules were substituted, responded declined gradually and eventually was poorly maintained. Ratio contingencies may not support responding as well as interval contingencies when electric shock is the maintaining event.     

Punishment-specific effects of pentobarbital: dependency on the type of punisher.

Pigeons were trained to peck a key under a multiple random-interval 1-minute, random-interval 6-minute schedule of food presentation. Subsequently, over three phases, additions were made during the random-interval 1-minute component as follows: pecks during the component occasionally were punished by timeout presentation (Phase 1), timeouts were presented independently of responding during the component (Phase 2), pecks during the component occasionally were punished by electric-shock presentation (Phase 3). In Phases 1 and 3, response-dependent timeout and shock suppressed responding and established equivalent rates in both components of the multiple schedule. Intermediate doses of pentobarbital increased responding suppressed by electric-shock punishment but had little or no effect on responding suppressed by timeout punishment. Response-independent presentation of timeouts did not result in suppression of responding (thus showing that response-dependent timeout acted as a punisher), and pentobarbital did not reliably increase unpunished responding. Pentobarbital's selective "punishment-attenuating" properties depend on the nature of the punisher.     

Roger T. Kelleher, behavior analyst

Roger T. Kelleher, rightly known as one of the foremost contributors to behavioral pharmacology, also made many important contributions to the experimental analysis of behavior. He participated significantly in the development of the discipline, through both his research and his editorial contributions to thisjournal. This article summarizes his contributions to the field of behavior analysis. His most significant empirical and conceptual contributions to behavior analysis came in two domains-conditioned reinforcement and the power of schedules of reinforcement. His accomplishments in these two domains still serve as principal foundations for modern research and theory.     

The many faces of self: ego and ethnic identities

This study addressed how adolescents come to develop a sense of ethnic identity. The author examined ethnic identity development as a process that occurs simultaneously with the development of ego identity and attitudes toward groups other than one's own. A multiethnic sample of 297 adolescents and young adults (aged 13 to 26 years) completed the Extended Objective Measure of Ego Identity Scale Revision 2 (EOMEIS2; L. Bennion & G. Adams, 1986), the Multigroup Ethnic Identity Measure (MEIM; J. Phinney, 1992), and the Other Group Orientation Scale (J. Phinney, 1992). An Age x Ethnic Group x Gender experimental design was used to determine whether these factors contributed differently to ethnic identity and ego identity. Analyses showed significant differences in the level of ethnic identity development among the ethnic groups. More pronounced age differences were found at the lower levels of ego identity development than at the more advanced levels.     

Tolerance to the effects of cocaine on performance under behavior-correlated reinforcement magnitude

Four pigeons responded under a fixed-interval 8-min schedule of food delivery in which the amount of food delivered at the end of each interval depended on performance during the interval (i.e., a correlated schedule). Specifically, duration of access to grain was contingent upon the number of responses made during the first 4 min of the interval. This differential outcome did not affect response rates or patterning relative to performance under a simple fixed-interval 8-min schedule. Behavior under the correlated schedule was then investigated under doses of cocaine ranging from 0.3 to 10.0 mg/kg. A bitonic dose-response function was obtained for response rates and the time with head in the food hopper, whereas dose-dependent decreases were observed in the mathematical index of curvature (Fry, Kelleher, & Cook, 1960). The dose that produced the greatest increase in the head-in-hopper time was then administered prior to each session. Following repeated administration of cocaine, disruptions in response patterning were attenuated for all 4 pigeons; tolerance was also observed to the rate-increasing effects and increased head-in-hopper time for 2 pigeons after chronic cocaine administration. Tolerance therefore developed despite the fact that the initial effect of cocaine was to increase the amount of food obtained.     

急性肺损伤/急性呼吸窘迫综合征诊断和治疗指南(2006)

急性肺损伤(ALI)/急性呼吸窘迫综合征(ARDS)是一种常见危重症,病死率极高,严重威胁重症患者的生命并影响其生存质量.尽管我国重症医学已有了长足发展,但对ALI/ARDS的认识和治疗状况尚不容乐观.中华医学会重症医学分会以循证医学证据为基础,采用国际通用的方法,经广泛征求意见和建议,反复认真讨论,达成关于成人ALI/ARDS诊断和治疗方面的共识,以期对成人ALI/ARDS诊断和治疗进行规范.中华医学会重症医学分会以后还将根据循证医学证据的发展及新的共识对ALI/ARDS诊断和治疗指南进行更新.     

The Many Faces of Self: Ego and Ethnic Identities

This study addressed how adolescents come to develop a sense of ethnic identity. The author examined ethnic identity development as a process that occurs simultaneously with the development of ego identity and attitudes toward groups other than one's own. A multiethnic sample of 297 adolescents and young adults (aged 13 to 26 years) completed the Extended Objective Measure of Ego Identity Scale Revision 2 (EOMEIS2; L. Bennion & G. Adams, 1986), the Multigroup Ethnic Identity Measure (MEIM; J. Phinney, 1992), and the Other Group Orientation Scale (J. Phinney, 1992). An Age x Ethnic Group x Gender experimental design was used to determine whether these factors contributed differently to ethnic identity and ego identity. Analyses showed significant differences in the level of ethnic identity development among the ethnic groups. More pronounced age differences were found at the lower levels of ego identity development than at the more advanced levels.     

Drug addiction. Is it a disease or is it based on choice? A review of Gene Heyman's Addiction: A disorder of choice.

In Addiction: A disorder of choice, Gene Heyman surveys a broad array of evidence—historical, anthropological, survey, clinical, and laboratory‐based to build an argument about the role of basic choice processes in the phenomena that comprise drug addiction. He makes a compelling, multifaceted argument that conceptualizing drug addiction as a chronic disease (like schizophrenia or diabetes) is both misleading and erroneous. In developing his argument, he points out that the best survey data available indicate that most drug addicts quit their addiction, a fact inconsistent with a chronic‐disease model. He illustrates how basic, normal choice processes can lead to addiction, arguing that people do not choose to be addicts, but that normal choice dynamics can lead them to that condition. He points to a variety of factors that keep most from becoming addicted, with a focus on the role of choice governed by choice‐by‐choice contingencies versus choice governed by the outcome of sequences of choices, a difference in an under‐described activity called framing. His view is consistent with the most effective treatments currently available, and provides a basis for continued basic research on choice as well as research on treatment and prevention.     

Support for anterior temporal involvement in semantic error production in aphasia: new evidence from VLSM

Semantic errors in aphasia (e.g., naming a horse as “dog”) frequently arise from faulty mapping of concepts onto lexical items. A recent study by our group used voxel-based lesion-symptom mapping (VLSM) methods with 64 patients with chronic aphasia to identify voxels that carry an association with semantic errors. The strongest associations were found in the left anterior temporal lobe (L-ATL), in the mid- to anterior MTG region. The absence of findings in Wernicke’s area was surprising, as were indications that ATL voxels made an essential contribution to the post-semantic stage of lexical access. In this follow-up study, we sought to validate these results by re-defining semantic errors in a manner that was less theory dependent and more consistent with prior lesion studies. As this change also increased the robustness of the dependent variable, it made it possible to perform additional statistical analyses that further refined the interpretation. The results strengthen the evidence for a causal relationship between ATL damage and lexically-based semantic errors in naming and lend confidence to the conclusion that chronic lesions in Wernicke’s area are not causally implicated in semantic error production.     

与癌共存安享欢乐生活

癌症是现代社会人群意外死亡的致命杀手,目前医学科学还没有完美预防和治疗它的措施和办法,恐惧、悲观、失望、焦虑是有害的,过度治疗也不可取,与癌共存,安享生活是值得提倡的理念。