Gestural development,dual-directional signaling,and the transition to words

This paper describes the emergence and development of three object-related gestures: pointing, extending objects, and open-handed reaching, in four first-born infants from 9 to 18 months during natural interactions with their mothers. It examines the changing characteristics of the gestures and the acquisition of conventional words in accompaniment. Furthermore, it investigates the role that the capacity for dual-directional signaling, sending simultaneously two coordinated but divergently directed nonverbal signals of gesture and gaze, may play in this transition. Analysis revealed that dual-directional signaling appeared concurrently across gestures. In addition, dual-directional signaling was employed in a socially adjusted manner, more with pointing, especially spontaneous pointing when the mothers' attention could not be assumed. Verbal accompaniments appeared with gestures only when the children had mastered dual-directional signaling. Then words emerged approximately simultaneously with more than one kind of gesture.     

AN ANALYSIS AND REDUCTION OF DISRUPTIVE BEHAVIOR ON SCHOOL BUSES

Thousands of children are injured or killed each year in school bus accidents. A significant number of these tragic incidents is precipitated by disruptive child behavior that distracts the drivers from their difficult task. Two experiments were conducted which addressed this problem. For both experiments an automated sound recording device (referred to as a Noise Guard) selectively responsive to frequencies above 500 Hz (i.e., unresponsive to bus drone) recorded both the duration and frequency of noise outbursts above a tolerable threshold. Additionally, an observer made in situ measurements of other disruptions including roughhousing and getting-out-of-seat. In the first experiment, following baseline measurements of these behaviors, middle-school students received feedback for noise outbursts. That is, when “Noise Guard'” was activated, it in turn operated one of several lights on a panel visible to all passengers. Each day students were allowed to listen to high-appeal taped music while riding the bus and to participate in a raffle for prizes, provided the number of outbursts on the preceding day remained below a specified criterion indicated on the light panel. This intervention resulted in drastic reductions of noise outbursts with a concomitant reduction in other disruptive behaviors. Comparable results were obtained in the second experiment which eliminated the raffle from the intervention.     

Depression in aphasic patients: Frequency, severity, and clinical-pathological correlations

Twenty-five hospitalized nonfluent, fluent, and global aphasic patients who were several months past the onset of their illness were compared for presence and severity of depression based on four psychopathological measures. The nonfluent aphasic patients had both greater frequency and severity of depression than the other two groups. CT scans showed that the global aphasic patients had the largest lesion size (volumetric) and showed a strong correlation between lesion size and degree of depression. In contrast, patients with fluent aphasias showed an inverse correlation between severity of depression and lesion size; among the nonfluent aphasic patients there was no significant correlation. Depression appears to be common in this population of hospitalized aphasic patients with chronic illness and nonfluent patients are the most depressed group within this population. The increased frequency and severity of depression in the nonfluent patients did not appear to be related to their overall physical or cognitive impairment; two possible mechanisms are discussed.     

Studies of mood and humor appreciation

A total of 189 students in two studies rated jokes on funniness and several other scales after rating their own mood on the Nowlis-Green Mood Adjective Check List. Subjects in Experiment 1 gave a second and third set of mood ratings after their joke-funniness ratings. Three mood factors—surgency, elation, and vigor—reliably predicted joke appreciation in both studies. More tentative evidence linked humor appreciation to concentration, social affection, excitement, freedom, and (lack of) fatigue, but humor appeared independent of aggression, anxiety, tension, and inhibition. Relationships among joke-scale ratings were highly similar for subjects reporting relatively positive moods and those reporting more negative moods. Results were discussed with reference to several humor theories.The authors would like to thank Carol Pierce, Marguerite Ponder, and Ron Fox for their help with this research.     

Developmental trends in the salience of meaning versus structural attributes of written words

Summary This study was designed to evaluate Gibson's contention that maximum sensitivity to the meanings of printed words does not occur until the individual has become a fluent reader. Also of interest was the degree to which reading ability would significantly influence the developmental course. These questions were evaluated by means of a sorting task which allowed subjects to group printed words on the basis of either semantic-syntactic (meaning) or graphic-phonologic (structural) attributes, and differential grouping tendencies along the age/grade continuum were the dependent measures specifically evaluated. Subjects consisted of normal and poor readers from grades 1–6, as well as ninth graders and college sophomores. The study was quasi-longitudinal in that available subjects from grades 2–5 were retested a year later to evaluate the reliability of developmental trends.Results were consistent with Gibson's theory. Sensitivity to word meanings was much more stable in fluent readers than it was in less fluent readers, although there was considerable individual variability noted at all levels. Poor readers were inclined to place words they could identify more often in meaning than in structural categories. However, structural categories that were utilized, were often idiosyncratic, suggesting that poor readers are less atuned to orthographic regularities than are normal readers.     

Imagery and olfactory stimulation

The purpose of the present study was to investigate a possible odor-emotion interaction by determining whether humans could differentially detect other humans' odor collected under varying emotional conditions. Odorants were collected from the axillary apocrine glands of four female donors, each of whom underwent different imagery induction procedures of anxiety, relaxation, and sexual arousal. The odorants were chemically preserved and later evaluated by 16 naive white male judges as to the presence of discriminatory odor cues. Judges' imagery was differentially related to the anxiety imagery-produced odorants but only for those produced by the most imaginative donors. The relaxation odorants of all donors were correlated. The judges were unable to detect the sexual imagery arousal odorants.     

Style in Philosophy: Parts II and III

The essential task of the philosophy of style is to uncover the irreducibility of the singular to any kind of universal, static structure or metalinguistic code. Style is not only a surplus element that exceeds propositional meaning, but also a clue of the ineradicable contingency of "intersubjective"-communicational relationships. The receiver must respect the unique individuality of the sender's style as what demonstrates the cognitive inexhaustibility of the world. Consequently, philosophy can no longer regard literature as foreign and incorrigible by asserting a radical difference of genre and thereby reserving truth exclusively for itself. Rather, I go on to argue, the difference is merely one of quantity . The picture of the world drawn by literature is simply fuller and richer than any comparatively monochromatic system of philosophical propositions. However, within the history of philosophy, there have been instances when the philosophical import of literature has been accorded its due. One example is the dialogical approach of early German Romanticism. The other example is a writer most frequently considered the purest thinker of philosophical sense and meaning – namely, Ludwig Wittgenstein. I conclude by reading Wittgenstein as a philosopher concerned, above all, with the ineffable that style reveals.     

Effects of Age on the Generalization and Incubation of Memory in the F344 Rat

Freezing (immobility) in the presence of aversive stimuli is a species-specific behavior that is used as an operational measure of fear. Conditioning of this response to discrete sensory stimuli and environmental context cues has been used as a tool to study the neuropsychology of memory dynamics and their development over the lifespan. Three age groups of F344 rats (3, 9, and 27 month) received tone–foot shock pairing (or tone only) in a distinctive chamber on two consecutive days. Separate subgroups of rats from each age group were then tested, at retention intervals of 1, 20, 40, or 60 days, for context-mediated fear in the environment in which they were trained, for generalization of the fear response to a novel chamber, and for fear of the tone. Beginning at day 20, the 27-month-old rats exhibited less freezing behavior than did younger rats when tested in the conditioning context. This age difference was a result of freezing behavior becoming progressively stronger with time in the two younger age groups, a phenomenon that has been referred to as memory incubation. Incubation of the contextual fear response was not detected in the old rats. In a novel context, all age groups exhibited significantly more freezing than did control animals. There was also pronounced incubation of this generalized freezing response, and the extent of incubation declined significantly with age. In the novel context, the freezing response to the tone was robust in all age groups and increased over time, in constant proportion to the degree of freezing elicited by the novel context itself, prior to tone onset. The fact that old animals are known to be relatively selectively impaired in forms of memory that depend on a functional hippocampus suggests a possible explanation for the reduced incubation effects seen in old rats; however, whether the increased expression of fear over time is mediated by a hippocampal-dependent memory consolidation process or whether it reflects a generalized increase in the gain of the circuitry mediating the fear response itself, remains to be determined.     

Bilateral Ablation of Auditory Cortex in Mongolian Gerbil Affects Discrimination of Frequency Modulated Tones but not of Pure Tones

This study examines the role of auditory cortex in the Mongolian gerbil in differential conditioning to pure tones and to linearly frequency-modulated (FM) tones by analyzing the effects of bilateral auditory cortex ablation. Learning behavior and performance were studied in a GO/NO-GO task aiming at avoidance of a mild foot shock by crossing a hurdle in a two-way shuttle box. Hurdle crossing as the conditioned response to the reinforced stimulus (CR+), as false alarm in response to the unreinforced stimulus (CR−), intertrial activity, and reaction times were monitored. The analysis revealed no effects of lesion on pure tone discrimination but impairment of FM tone discrimination. In the latter case lesion effects were dependent on timing of lesion relative to FM tone discrimination training. Lesions before training in naive animals led to a reduced CR+ rate and had no effect on CR− rate. Lesions in pretrained animals led to an increased CR− rate without effects on the CR+ rate. The results suggest that auditory cortex plays a more critical role in discrimination of FM tones than in discrimination of pure tones. The different lesion effects on FM tone discrimination before and after training are compatible with both the hypothesis of a purely sensory deficit in FM tone processing and the hypothesis of a differential involvement of auditory cortex in acquisition and retention, respectively.     

Nosology and Causal Necessity; The Relation BetweenDefining a Disease and Discovering its Necessary Cause

The problem of disease definition is related to theproblem of proving that a certain agent is thenecessary cause of a certain disease. Natural kindterms like rheumatoid arthritis and AIDS refer toessences which are discoverable rather thanpredeterminate. No statement about such diseases isa priori necessarily true. Because theories onnecessary causes involve natural kind semantics,Koch's postulates cannot be used to falsify or verifysuch theories. Instead of proving that agent A is thenecessary cause of disease D, we include A in atheoretical definition of D, take this to representthe real meaning of D, and discard thepretheoretical definition. This is illustrated byKoch's own attempt to prove he had discovered thenecessary cause of tuberculosis. Methodologicalarguments about disease causation require a clear viewof our use of diagnostic terms. Medical lexicographersshould do more to provide such a view.