The underlying changes in heart coherence that are associated with reported EEG changes in response to meditation have been explored. We measured EEG and heart rate variability (HRV) before and during autogenic meditation. Fourteen subjects participated in the study. Heart coherence scores were significantly increased during meditation compared to the baseline. We found near significant decrease in high beta absolute power, increase in alpha relative power and significant increases in lower (alpha) and higher (above beta) band coherence during 3~min epochs of heart coherent meditation compared to 3~min epochs of heart non-coherence at baseline. The coherence and relative power increase in alpha band and absolute power decrease in high beta band could reflect relaxation state during the heart coherent meditation. The coherence increase in the higher (above beta) band could reflect cortico-cortical local integration and thereby affect cognitive reorganization, simultaneously with relaxation. Further research is still needed for a confirmation of heart coherence as a simple window for the meditative state.

Antidepressant overdose is associated with impaired heart rate variability in a pattern consistent with excess cardiac sympathetic activity. Further work is required to establish the significance of these findings and to explore whether the impairment of heart rate variability may be used to predict the development of arrhythmia in this patient group.

xv + 279 pages + reference + index) £37.50, hardback, ISBN 0-521-48158-9 1998, £14.95, softback, ISBN 0-521-63999-9 Carruthers in this book undertakes a very impressive project. He explains consciousness by assigning to language the crucial function in thought processes. He claims: (1) thoughts are conducted in natural language: they are expressed and stored in the form of language sentences.(2) Consciousness consists of the accessibility-relation of thoughts in virtue of the cognitive apparatus which has emerged through the evolution processes. Natural language is crucial to conscious thoughts on account of its representational potential. With this framework elucidating consciousness in terms of a linguistic mode of thought, the most recent programme of cognitive study in which our mind is more and more integrated into the order of nature can take a decisive step forward.The topic of this book is the subject of a long lasting debate dating back to antiquity: how are language and thought related to one another? While there has been general consensus that language-performance requires thought, it is controversial whether thought, in turn, is independent of language or involves natural language. The author argues for the latter position in a well-developed form.The central thesis of the book is that natural language is constitutively involved in conscious thought. According to the author, natural language is itself the primary medium of thought, and thinking is essentially linguistic. The trains of reasoning which lead to many of our decisions and actions consist of sequences of sentences. When a speaker utters a sentence, the utterance expresses a thought by constituting it, not by encoding or signalling it. Carruthers thus accords a central place to our language within human cognition. He refers to this approach as the cognitive conception of language. Opposed to this approach is the position of the communicative conception of language which claims that the function and purpose of our language is to facilitate communication and not to facilitate thinking.According to the 'Mentalese' thesis of Fodor, the central processing of cognition is conducted in Mentalese, a language of thought which is an innate and universal representational system in the mind. Natural language is but an isolated input and output module to that central cognition, i.e. not implicated in the central processes of thinking and reasoning themselves. It merely serves as a means of mediating interpersonally meanings of thoughts which have been already conducted in Mentalese. Fodor thus maintains with his