Perceptual organization of acoustic stimuli by budgerigars (Melopsittacus undulatus): III. Contact calls

We trained budgerigars by operant conditioning to discriminate among a set of contact calls in a same-different task and analyzed response latencies from this task by using multidimensional-scaling (MDS) and cluster-analysis procedures. Humans listened to the same calls and indicated the similarity between pairs of calls by a direct rating procedure. An MDS program (sindscal) was used to arrange these complex acoustic stimuli in multidimensional space reflecting perceptual organization. Multiple regression techniques were used to identify the acoustic characteristics of contact calls that were correlated with the perceptual dimensions obtained from MDS. A number of spectral characteristics (e.g., peak frequency, rate of frequency modulation, and concentration of spectral energy) emerged as important for both budgerigars and humans, but the relative salience of these cues differed for the two species. Additional tests with two groups of budgerigars--cagemates and noncagemates--showed that experience with calls can change the salience of various acoustic characteristics used for perceptual organization and individual recognition.     

Comprehension of sentence structure in anomic and conduction aphasia

Picture-pointing auditory and reading comprehension tests were administered to anomic and conduction aphasics. Subjects responded to active sentences of the present progressive form. The possible errors which a subject could make on these experimental tasks included failure to correctly interpret noun order, number, or lexical meaning. Both groups made significantly more correct responses than error responses. Of their error responses, noun-order errors significantly exceeded number and lexical errors for which no differences were observed. When compared with results previously obtained for agrammatic Broca's aphasics, no differences in the pattern of errors were identified. These results are discussed relative to current theories of syntactic processing and for the mechanisms which account for these syntactic comprehension deficits following aphasia.     

The relationship of social power to visual displays of dominance between men and women

Two studies, with undergraduate subjects, investigated how sex and situation-specific power factors relate to visual behavior in mixed-sex interactions. The power variable in Study 1 was expert power, based on differential knowledge. Mixed-sex dyads were formed such that members had complementary areas of expertise. In Study 2, reward power was manipulated. Consistent with expectation states theory, both men and women high in expertise or reward power displayed high visual dominance, defined as the ratio of looking while speaking to looking while listening. Specifically, men and women high in expertise or reward power exhibited equivalent levels of looking while speaking and looking while listening. High visual dominance ratios have been associated with high social power in previous research. Both men and women low in expertise or reward power looked more while listening than while speaking, producing a relatively low visual dominance ratio. In conditions in which men and women did not possess differential expertise or reward power, visual behavior was related to sex. Men displayed visual behavior similar to their patterns in the high expertise and high reward power conditions, whereas women exhibited visual behavior similar to their patterns in the low expertise and low reward power conditions. The results demonstrate how social expectations are reflected in nonverbal power displays.     

A case of hysteria, with a note on biology

Psychoanalysis recently has shown interest in the data of neurobiology. This interest has been fostered by the realization that a model of Cartesian mind-body dualism is inadequate to current observation and knowledge. Despite the theoretical appeal of integrating knowledge from the two fields, there have been few attempts at correlation in specific clinical situations. This paper presents a case of hysteria in which the physical manifestations of hyperprolactinemia, galactorrhea, amenorrhea, and infertility are considered in relation to both the brain regulation of prolactin and to unconscious fantasy, motivation, and conflict. Some of the intriguing possibilities and limitations of research at the frontier of psychoanalysis and neurophysiology are discussed.     

Does social exclusion motivate interpersonal reconnection? Resolving the "porcupine problem"

Evidence from 6 experiments supports the social reconnection hypothesis, which posits that the experience of social exclusion increases the motivation to forge social bonds with new sources of potential affiliation. Threat of social exclusion led participants to express greater interest in making new friends, to increase their desire to work with others, to form more positive impressions of novel social targets, and to assign greater rewards to new interaction partners. Findings also suggest potential boundary conditions to the social reconnection hypothesis. Excluded individuals did not seem to seek reconnection with the specific perpetrators of exclusion or with novel partners with whom no face-to-face interaction was anticipated. Furthermore, fear of negative evaluation moderated responses to exclusion such that participants low in fear of negative evaluation responded to new interaction partners in an affiliative fashion, whereas participants high in fear of negative evaluation did not.     

Human lumbar cord circuitries can be activated by extrinsic tonic input to generate locomotor-like activity

We have demonstrated that non-patterned electrical stimulation of the lumbar cord can induce stepping-like activity in the lower limbs of complete spinal cord injured individuals. This result suggested the existence of a human lumbar locomotor pattern generator, which can convert a tonic input to a rhythmic motor output. We have studied the human lumbar cord in isolation from supraspinal input but under extrinsic tonic input delivered by spinal cord stimulation. Large-diameter afferents within the posterior roots are directly depolarized by the electrical stimulation. These afferents project to motoneurons as well as to lumbar interneurons involved in the motor control of lower limbs. Stimulation at 25-50 Hz can elicit rhythmic alternating flexion/extension movements of the lower limbs in supine individuals. Reducing the tonic input frequency to 5-15 Hz initiates lower limb extension. Epidural stimulation applied during manually assisted treadmill stepping in complete spinal cord injured persons immediately increases the central state of excitability of lumbar cord networks and enhances stepping-like functional motor outputs. Sustained, non-patterned tonic input via the posterior roots can activate human lumbar cord networks. Pattern generating configurations of these multifunctional circuitries can be set-up depending on the stimulation parameters and particularly on the input frequency.     

Peer Victimization in Youth with Tourette’s Syndrome and Chronic Tic Disorder: Relations with Tic Severity and Internalizing Symptoms

The present study analyzed rates of peer victimization in children with a chronic tic disorder as compared to children with type 1 diabetes and healthy controls. The associations among peer victimization, tic symptom severity, and psychological symptoms, as well as the potential mediating relationship between peer victimization, tic severity, and child internalizing symptoms, were also explored. Children with tics displayed higher rates of peer victimization than control groups, and peer victimization in children with tics was positively correlated with tic symptom severity, loneliness, anxiety symptoms, and parent report of child internalizing symptoms. Results also supported the hypothesis that peer victimization mediates the relationship between tic symptom severity and loneliness. Findings highlight the importance of the assessment and treatment of psychosocial variables in children with chronic tic disorders, including social functioning and peer relationships.     

The Predictive Utility of Narcissism among Childrenand Adolescents: Evidence for a Distinction betweenAdaptive and Maladaptive Narcissism

We examined the predictive utility of narcissism among a community sample of children and adolescents (N=98) longitudinally. Analyses focused on the differential utility between maladaptive and adaptive narcissism for predicting later delinquency. Maladaptive narcissism significantly predicted self-reported delinquency at one-, two-, and three-year follow-ups. This pattern held even when considering other intrapersonal risk factors for conduct problems (i.e., callous-unemotional traits, impulsivity), parenting practices, and when controlling for earlier conduct problems. In addition, adaptive narcissism was predictive of delinquency in the absence of positive parenting practices, with maladaptive narcissism being particularly predictive of delinquency in the presence of negative parenting. The implications for understanding delinquency in terms of the social and motivational characteristics that are the hallmark of maladaptive narcissism are discussed.