Fluent versus nonfluent primary progressive aphasia: a comparison of clinical and functional neuroimaging features

To better characterize fluent and nonfluent variants of primary progressive aphasia (PPA). Although investigators have recognized both fluent and nonfluent patients with PPA, the clinical and neuroimaging features of these variants have not been fully defined. We present clinical and neuropsychological data on 47 PPA patients comparing the fluent (n=21) and nonfluent (n=26) subjects. We further compared language features with PET/SPECT data available on 39 of these patients. Compared to the nonfluent PPA patients, those with fluent PPA had greater impairment of confrontational naming and loss of single word comprehension. They also exhibited semantic paraphasic errors and loss of single word comprehension. Patients with nonfluent PPA were more likely to be female, were more often dysarthric, and exhibited phonological speech errors in the absence of semantic errors. No significant differences were seen with regard to left hemisphere abnormalities, suggesting that both variants result from mechanisms that overlap frontal, temporal, and parietal regions. Of the language measures, only semantic paraphasias were strongly localized, in this case to the left temporal lobe. Fluent and nonfluent forms of PPA are clinically distinguishable by letter fluency, single word comprehension, object naming, and types of paraphasic errors. Nevertheless, there is a large amount of overlap between dysfunctional anatomic regions associated with these syndromes.     

The interplay between goal intentions and implementation intentions

Two studies tested whether action control by implementation intentions is sensitive to the activation and strength of participants' underlying goal intentions. In Study 1, participants formed implementation intentions (or did not) and their goal intentions were measured. Findings revealed a significant interaction between implementation intentions and the strength of respective goal intentions. Implementation intentions benefited the rate of goal attainment when participants had strong goal intentions but not when goal intentions were weak. Study 2 activated either a task-relevant or a neutral goal outside of participants' conscious awareness and found that implementation intentions affected performance only when the relevant goal had been activated. These findings indicate that the rate of goal attainment engendered by implementation intentions takes account of the state (strength, activation) of people's superordinate goal intentions.     

Logical Truth and Tarskian Logical Truth

This paper examines the question of the extensional correctness of Tarskian definitions of logical truth and logical consequence. I identify a few different informal properties which are necessary for a sentence to be an informal logical truth and look at whether they are necessary properties of Tarskian logical truths. I examine arguments by John Etchemendy and Vann McGee to the effect that some of those properties are not necessary properties of some Tarskian logical truths, and find them unconvincing. I stress the point that since the hypothesis that Tarski's definitions are extensionally correct is deeply entrenched, the burden of proof is still on the shoulders of Tarski's critics, who have not lifted the burden. This revised version was published online in June 2006 with corrections to the Cover Date.     

Enrique Dussel,The Invention of the Americas: Eclipse of“the Other”and the Myth of Modernity

Continental Philosophy Review -     

Archetypes and Spirits: A Jungian Analysis of Puerto Rican Espiritismo

In this paper a comparison is made between Jung's approach to healing with a traditional healing system practised in Puerto Rico, called ‘Espiritismo’. Jungian psychology and ‘Espiritismo’ have several strong similarities in their conception of the therapeutic process, similarities which suggest that the healing process itself has generic properties which can be found in several therapeutic systems. In addition, by analysing Jung's development as a healer, it is possible to draw parallels between his development as a psychotherapist and the process of becoming a spiritist healer. In both healing systems, a transpersonal dimension is recognized as an integral element in the healing process. In ‘Espiritismo’, the suffering individual has to confront the spirit world; in analytical psychotherapy the patient has to confront the collective unconscious. This parallel was explicitly recognized by Jung in his autobiography when he compared the collective unconscious with the land of the dead. For Jung, knowledge of the figures of the unconscious enormously facilitates the individuation process; in ‘Espiritismo’ it is necessary to know the spirit world and to establish a relationship with the spirits. In Jungian psychology, healing is a process of ‘exorcizing’ some types of complexes or integrating others to consciousness. On the other hand, spiritist healers ‘exorcize’ ignorant spirits in order to heal a client or help him/her to identify spirit guides. In both systems, healing is essentially a process of establishing a dialogue with a transpersonal dimension (archetypes or spirits). Healing in ‘Espiritismo’ and Jungian psychology is a process of transcending the limited perspective of the ego (the ‘material world’) in order to experience a much broader reality (spiritual world or collective unconscious). Both systems emphasize the need to work with resources beyond the boundaries of the ego and to connect with forces that belong to a different reality.     

The physicist and philosophy

Journal for General Philosophy of Science - The central thesis of this paper is that physicists have as much to learn from scientifically oriented philosophy as philosophers have to learn from...     

Medical diagnostic reasoning: Epistemological modeling as a strategy for design of computer-based consultation programs

The complexity of cognitive emulation of human diagnostic reasoning is the major challenge in the implementation of computer-based programs for diagnostic advice in medicine. We here present an epistemological model of diagnosis with the ultimate goal of defining a high-level language for cognitive and computational primitives. The diagnostic task proceeds through three different phases: hypotheses generation, hypotheses testing and hypotheses closure. Hypotheses generation has the inferential form of abduction (from findings to hypotheses) constrained under the criterion of plausibility. Hypotheses testing is achieved by a deductive inference (from generated hypotheses to expected findings), followed by an eliminative induction, constrained under the criterion of covering, which matches expected findings against patient's findings to select the best explanation. Hypotheses closure is a deductive-inductive type of inference very similar to the inferences operating in hypotheses testing. In this case induction matches the consequences of the generated hypotheses against the patient's characteristics or preferences under the criterion of utility. By using the language exploited in this epistemological model, it is possible to describe the cognitive tasks underlying the most influential knowledge-based diagnostic systems.