Low-dimensional chaos maps learning in a model neuropil (olfactory bulb)

Quantification of a chaotic system can be made by calculating the correlation dimension (D2) of the data that the system generates (Packard et al., 1980). The D2 algorithm, however, requires stationarity of the generator, a feature that biological data rarely reflect (Mayer-Kress et al., 1988). So we developed the “point correlation dimension” (PD2), an algorithm that accurately tracks D2 in linked data of different dimensions (Carpeggiani et al., 1991). We now present a mathematical argument that, for stationary data, individual PD2s converge to D2 and we demonstrate that the algorithm rejects contributions made by bursts of noise. Data were obtained from the surface of the olfactory bulb of the conscious rabbit (64 electrodes, 640 Hz each, 1.3 sec epochs) before and after presentation of a novel or habituated odor. D2 could be calculated in only 1 of 10 novel-odor trials, whereas PD2 could be calculated in all. Both algorithms indicated that a novel odor evokes a spatially uniform dimensional increase. The PD2 uniquely exhibited the dimensional decreases that occur during inspiration and the gradients of mean dimension present during the nonstimulated control state. These control gradients remained unchanged without odor experience, but showed spatially specific PD2 increases following odor habituation. It is interpreted that, 1) the PD2 issensitive, accurate, and appropriate for dimensional assessment of biological data, 2) that during analysis of unfamiliar information a singleglobal process is transiently evoked in the neuropil, and 3) after experience multiplespatially specific processes tonically map the sites of learning. Grant Support: National Institutes of Health, HL 31164 and NS27745     

TOWARD A NEW RELATION BETWEEN HUMANITY AND NATURE: RECONSTRUCTING T'IEN-JEN-HO-I

Abstract. The traditional Chinese idea of t'ien-jen-ho-i (Heaven and humanity in union) implies that humanity has to live in harmony with nature. As science and technology progress, however, the idea appears increasingly outmoded, and it becomes fashionable to talk about overcoming nature. Ironically, though, the further science reaches the more clearly are its limitations exposed. The exploitation of nature not only endangers many life forms on earth but threatens the very existence of the human species. I propose that a reconstruction of the traditional Chinese idea of T'ien-jen-ho-i will help us envisage a new and salutary relation between humanity and nature.     

单眼视剥夺2小时对雏鸡记忆保持的影响

以2日龄雏鸡为研究对象,采用一次性被动回避学习模型,以不透明胶纸封贴一侧眼的方法,研究2日龄雏鸡单侧眼视剥夺2小时后对视觉学习记忆的影响,并与双眼学习条件下的记忆情况进行比较;试图探讨雏鸡在视觉信息加工过程中左、右半球的作用。实验结果表明：剥夺一侧眼（无论左或右）2小时后对雏鸡的短时记忆无影响,明显干扰雏鸡的中期和长时记忆,特别是剥夺左眼干扰更明显。     

Changes in Anxiety Control Beliefs Following a Brief CBT Treatment and Their Association With Anxiety Symptom Reduction

Anxiety control beliefs (i.e., beliefs regarding one’s ability to cope with external, fear-inducing threats and internal reactions to those perceived threats) have been found to negatively predict anxiety symptoms in children and adults and to be modifiable by cognitive-behavioral therapy for anxiety disorders. The current study examines whether changes in anxiety control beliefs were seen following a brief, intensive treatment for specific phobias, and whether those changes were associated with improvements in the targeted phobia and comorbid anxiety disorder symptoms. Participants were 135 children and adolescents (M age = 9.01 years, 49% male) who received one-session treatment (OST) with or without parental involvement for their primary specific phobia. Results indicated that self-reported anxiety control beliefs significantly increased following treatment and that these increases significantly predicted reductions in specific phobia severity and symptoms of comorbid anxiety disorders 6 months and 1 year following treatment. Findings illustrate that involvement in a single 3-hour OST was associated with changes in anxiety control beliefs and demonstrate the potential importance of targeting control beliefs in pediatric anxiety treatment.     

Differential acquisition of lever pressing in inbred and outbred mice: comparison of one-lever and two-lever procedures and correlation with differences in locomotor activity

Recent progress in mouse genetics has led to an increased interest in developing procedures for assessing mouse behavior, but relatively few of the behavioral procedures developed involve positively reinforced operant behavior. When operant methods are used, nose poking, not lever pressing, is the target response. In the current study differential acquisition of milk-reinforced lever pressing was observed in five inbred strains (C57BL/6J, DBA/2J, 129X1/SvJ, C3H/HeJ, and BALB/cJ) and one outbred stock (CD-1) of mice. Regardless of whether one or two levers (an "operative" and "inoperative" lever) were in the operant chamber, a concomitant variable-time fixed-ratio schedule of milk reinforcement established lever pressing in the majority of mice within two 120-min sessions. Substantial differences in lever pressing were observed across mice and between procedures. Adding an inoperative lever retarded acquisition in C57BL/6J, DBA/2J, 129X1/SvJ, and C3H/HeJ mice, but not in CD-1 and BALB/cJ mice. Locomotor activity was positively correlated with number of lever presses in both procedures. Analyses of durations of the subcomponents (e.g., time to move from hopper to lever) of operant behavior revealed further differences among the six types of mice. Together, the data suggest that appetitively reinforced lever pressing can be acquired rapidly in mice and that a combination of procedural, behavioral, and genetic variables contributes to this acquisition.     

PUNISHMENT IN HUMAN CHOICE: DIRECT OR COMPETITIVE SUPPRESSION?

This investigation compared the predictions of two models describing the integration of reinforcement and punishment effects in operant choice. Deluty's (1976) competitive-suppression model (conceptually related to two-factor punishment theories) and de Villiers' (1980) direct-suppression model (conceptually related to one-factor punishment theories) have been tested previously in nonhumans but not at the individual level in humans. Mouse clicking by college students was maintained in a two-alternative concurrent schedule of variable-interval money reinforcement. Punishment consisted of variable-interval money losses. Experiment 1 verified that money loss was an effective punisher in this context. Experiment 2 consisted of qualitative model comparisons similar to those used in previous studies involving nonhumans. Following a no-punishment baseline, punishment was superimposed upon both response alternatives. Under schedule values for which the direct-suppression model, but not the competitive-suppression model, predicted distinct shifts from baseline performance, or vice versa, 12 of 14 individual-subject functions, generated by 7 subjects, supported the direct-suppression model. When the punishment models were converted to the form of the generalized matching law, least-squares linear regression fits for a direct-suppression model were superior to those of a competitive-suppression model for 6 of 7 subjects. In Experiment 3, a more thorough quantitative test of the modified models, fits for a direct-suppression model were superior in 11 of 13 cases. These results correspond well to those of investigations conducted with nonhumans and provide the first individual-subject evidence that a direct-suppression model, evaluated both qualitatively and quantitatively, describes human punishment better than a competitive-suppression model. We discuss implications for developing better punishment models and future investigations of punishment in human choice.     

Global and local covert visual attention: Evidence from a bayesian hidden markov model

Psychological, psychophysical and physiological research indicates that people switch between two covert attention states, local and global attention, while visually exploring complex scenes. The focus in the local attention state is on specific aspects and details of the scene, and on examining its content with greater visual detail. The focus in the global attention state is on exploring the informative and perceptually salient areas of the scene, and possibly on integrating the information contained therein. The existence of these two visual attention states, their relative prevalence and sequence in time has remained empirically untested to date. To fill this gap, we develop a psychometric model of visual covert attention that extends recent work on hidden Markov models, and we test it using eye-movement data. The model aims to describe the observed time series of saccades typically collected in eye-movement research by assuming a latent Markov process, indicative of the brain switching between global and local covert attention. We allow subjects to be in either state while exploring a stimulus visually, and to switch between them an arbitrary number of times. We relax the no-memory-property of the Markov chain. The model that we develop is estimated with MCMC methodology and calibrated on eye-movement data collected in a study of consumers' attention to print advertisements in magazines.We thank Dominique Claessens of Verify International for making the data available to us.     

中医隐性知识结构维度模型的验证性研究

隐性知识大量存在于中医医者知识体系中。深入探讨中医医者隐性知识的结构维度,有利于中医的传承及个体隐性知识的转移。通过文献分析和专家访谈,发现中医隐性知识可以分为学习策略维度、临床技能维度、人际互动维度、情绪情感维度、价值取向维度和中医药文化维度。结合各维度之间的相互关系,构建了中医隐性知识的结构模型。为了提升该维度结构模型的科学性,对国家级名老中医、国医大师、中医院管理者进行了深度访谈和问卷调查,进行了验证性研究。