Davidson on First-Person Authority

Davidson's explanation of first-person authority in utterance of sentences of the form 'I V that p ' derives first-person authority from the requirements of interpretation of speech. His account is committed to the view that utterance sentences are truth-bearers, that believing that p is a matter of holding true an utterance sentence, and that a speaker's knowledge of what he means gives him knowledge of what belief he expresses by his utterance. These claims are here faulted. His explanation of first-person authority by reference to the requirements of interpretability is committed to the view that all understanding involves interpretation. This is argued to be a misconception of understanding and of speaker's meaning. Davidson's account involves acceptance of the cognitive assumption that normally when a person V s that p , he knows that he does. This assumption is challenged. Throughout, Davidson's conception is compared and contrasted with Wittgenstein's.     

Encoding, repetition, and the mirror effect in recognition memory: Symmetry in motion

Attention/likelihood theory has been used to explain the mirror effect in recognition memory. The theory also predicts that any manipulation that affects the recognition of old items will also affect recognition of the new items—more specifically, that all the underlying distributions will move and that they will move symmetrically on the decision axis. In five experiments, we tested this prediction. The first two experiments used encoding tasks during study to change recognition performance for high- and low-frequency words. The results show symmetrical dispersion of the underlying distributions. The final three experiments used repetition to increase recognition performance. Repetition produced a symmetrical pattern of movement that was different from that produced by encoding task. This pattern is, however, also covered by attention/likelihood theory. A further extension of the theory was used to predict response times.     

The Use of Contextual Information by Right Brain-Damaged Individuals in the Resolution of Ambiguous Pronouns

Two experiments were conducted with the primary purpose of investigating the ability of right brain-damaged (RBD) individuals to use contextual information—at the level of the single sentence, in terms of the integration of information between clauses, and at the level of a minimal discourse (i.e., two sentences)—in the resolution of ambiguous pronouns. The investigation was extended to a group of left brain-damaged (LBD) and non-brain-damaged (NBD) individuals. Contrary to the prevailing view that RBD patients have difficulty in the use of contextual information to process language, both experiments were consistent in demonstrating that the RBD group was influenced by contextual information in a manner similar to that demonstrated by both the LBD and NBD groups.     

Compensation for Jaw Fixation by Aphasic Patients

The ability to compensate for fixation of the jaw by a bite block was investigated in 6 nonfluent aphasics, 6 fluent aphasics, and 10 normal control subjects. Acoustic analyses of the vowels [i u a æ] and fricatives [s s] revealed substantial but incomplete compensation for the perturbation in all three subject groups. Perceptual identification scores and quality ratings by naive and phonetically trained listeners indicated poorer identification of the high vowels [i u] under compensatory conditions relative to normal production. Of particular interest was the fact that all three groups of subjects exhibited similar patterns of results. The findings suggest that any deficit in speech motor programming demonstrated by the nonfluent aphasic patients did not affect compensatory abilities. Results are discussed with respect to normal speech adaptation skills and the nature of articulatory breakdown in nonfluent aphasia.     

Effects of Different Telephone Intervention Styles with Suicidal Callers at Two Suicide Prevention Centers: An Empirical Investigation

To determine the relative effectiveness of telephone intervention styles with suicidal callers, researchers listened unobtrusively to 617 calls by suicidal persons at two suicide prevention centers and categorized all 66,953 responses by the 110 volunteer helpers according to a reliable 20-category checklist. Outcome measures showed observer evaluations of decreased depressive mood from the beginning to the end in 14% of calls, decreased suicidal urgency ratings from the beginning to the end in 27% of calls, and reaching a contract in 68% of calls, of which 54% of contracts were upheld according to follow-up data. Within the context of relatively directive interventions, a greater proportion of Rogerian nondirective responses was related to significantly more decreases in depression. Reduction in urgency and reaching a contract were related to greater use of Rogerian response categories only with nonchronic callers.     

Automation bias: decision making and performance in high-tech cockpits

Automated aids and decision support tools are rapidly becoming indispensable tools in high-technology cockpits and are assuming increasing control of"cognitive" flight tasks, such as calculating fuel-efficient routes, navigating, or detecting and diagnosing system malfunctions and abnormalities. This study was designed to investigate automation bias, a recently documented factor in the use of automated aids and decision support systems. The term refers to omission and commission errors resulting from the use of automated cues as a heuristic replacement for vigilant information seeking and processing. Glass-cockpit pilots flew flight scenarios involving automation events or opportunities for automation-related omission and commission errors. Although experimentally manipulated accountability demands did not significantly impact performance, post hoc analyses revealed that those pilots who reported an internalized perception of "accountability" for their performance and strategies of interaction with the automation were significantly more likely to double-check automated functioning against other cues and less likely to commit errors than those who did not share this perception. Pilots were also lilkely to erroneously "remember" the presence of expected cues when describing their decision-making processes.     

Hippocampal synaptic plasticity during instrumental learning

present research examined the role of hippocampal NMDA-dependent synaptic potentiation on appetitive instrumental conditioning under a continuous reinforcement schedule. In the first experiment, low (.025 mg.kg) or moderate (.05 mg/kg) dosages of the NMDA receptor antagonist, MK801, failed to increase the number of training days required to reach acquisition criterion; number of training days required to reach criterion for extinction were also unaffected. In the second experiment, a higher dosage (.10 mg/kg) of MK801 or induction of long-term potentiation failed to alter the number of responses occurring during acquisition. These data suggest that hippocampal synaptic potentiation does not play a prominent role in instrumental learning with simple contingency conditions. It is suggested that hippocampal LTP reflects a perceptual process that contributes differentially to spatial cognition, classical and instrumental conditioning.