For further development of organic agriculture, it will become increasingly essential to integrate experienced innovative practitioners in research projects. The characteristics of this process of co-learning have been transformed into a research approach, theoretically conceptualized as “experiential science” (Baars 2007 , Baars and Baars 2007 ). The approach integrates social sciences, natural sciences, and human sciences. It is derived from action research and belongs to the wider field of transdiscliplinary research. In a dialogue-based culture of equality and (...) mutual exchange the principal of a “bottom-up” experiential learning process can be stimulated and fully reflective. It provides an opportunity to develop organic agriculture as multiple best-practices based on transdisciplinary projects, cases studies, and case series. The aim of the article is to describe the methodological characteristics and the theoretical and practical potential of experiential science for research in and development of organic farming. Three characteristic projects are outlined to illustrate the main elements of the methodology: the retrospective reflection on intuitive and experiential knowledge held by farmers; the knowledge derived from on-farm experimentation; the exchange of knowledge and experiences between farming pioneers within a “masterclass” setting. The study concludes that experiential science offers an important philosophical reconciliation process whereby a synthesis of different approaches to research becomes possible in solving real-life problems: quantitative and qualitative, subjective and objective, reductionistic and holistic, practice and science. Recognizing that there are multiple elements contributing to the process of acquiring knowledge, experiential science draws on a broad field of scientific methods thereby integrating the hermeneutic approach of social sciences and the Humanities with the established methods of contemporary natural science. (shrink)
Producers, traders, and consumers oforganic food regularly use the concept of thenatural (naturalness) to characterize organicagriculture and or organic food, in contrast tothe unnaturalness of conventional agriculture.Critics sometimes argue that such use lacks anyrational (scientific) basis and only refers tosentiment. In our project, we made an attemptto clarify the content and the use of theconcepts of nature and naturalness in organicagriculture, to relate this conception todiscussions within bioethical literature, andto draw the implications for agriculturalpractice and policy.Qualitative interviews were executed with (...) arange of people in the field of organicagriculture and with consumers of organicproducts, on the basis of a list of statementsabout the meaning of the concept of naturalnessformulated by the authors. Based on the resultsof the interviews, we distinguished 3 aspectsof the concept of naturalness: natural as theorganic (life processes), natural as theecological, and natural as referring to thecharacteristic nature of an entity. We relatedthese conceptual aspects to three mainapproaches within the field of organicagriculture: the no chemicals approach, theagro-ecological approach, and the integrityapproach. It became clear that these approachescan also be recognized in the change ofattitude of farmers as they convert fromconventional to organic agriculture, and in theattitudes of consumers of organic foodproducts. (shrink)
Conscious experience is one of the most difficult and thorny problems in psychological science. Its study has been neglected for many years, either because it was thought to be too difficult, or because the relevant evidence was thought to be poor. Bernard Baars suggests a way to specify empirical constraints on a theory of consciousness by contrasting well-established conscious phenomena - such as stimulus representations known to be attended, perceptual, and informative - with closely comparable unconscious ones - such (...) as stimulus representations known to be preperceptual, unattended, or habituated. Adducing data to show that consciousness is associated with a kind of global workplace in the nervous system, and that several brain structures are known to behave in accordance with his theory, Baars helps to clarify many difficult problems. (shrink)
Conscious events interact with memory systems in learning, rehearsal and retrieval (Ebbinghaus 1885/1964; Tulving 1985). Here we present hypotheses that arise from the IDA computional model (Franklin,Kelemen and McCauley 1998; Franklin 2001b) of global workspace theory (Baars 1988, 2002). Our primary tool for this exploration is a flexible cognitive cycle employed by the IDA computational model and hypothesized to be a basic element of human cognitive processing. Since cognitive cycles are hypothesized to occur five to tentimes a second and (...) include interaction between conscious contents and several of the memory systems, they provide the means for an exceptionally fine-grained analysis of various cognitive tasks. We apply this tool to the small effect size of subliminal learning compared to supraliminal learning, to process dissociation, to implicit learning, to recognition vs. recall, and to the availability heuristic in recall. The IDA model elucidates the role of consciousness in the updating of perceptual memory, transient episodic memory, and procedural memory. In most cases, memory is hypothesized to interact with conscious events for its normal functioning. The methodology of the paper is unusual in that the hypotheses and explanations presented are derived from an empirically based, but broad and qualitative computational model of human cognition. (shrink)
This paper explores a remarkable convergence of ideas and evidence, previously presented in separate places by its authors. That convergence has now become so persuasive that we believe we are working within substantially the same broad framework. Taylor's mathematical papers on neuronal systems involved in consciousness dovetail well with work by Newman and Baars on the thalamocortical system, suggesting a brain mechanism much like the global workspace architecture developed by Baars (see references below). This architecture is relational, in (...) the sense that it continuously mediates the interaction of input with memory. While our approaches overlap in a number of ways, each of us tends to focus on different areas of detail. What is most striking, and we believe significant, is the extent of consensus, which we believe to be consistent with other contemporary approaches by Weiskrantz, Gray, Crick and Koch, Edelman, Gazzaniga, Newell and colleagues, Posner, Baddeley, and a number of others. We suggest that cognitive neuroscience is moving toward a shared understanding of consciousness in the brain. (shrink)
1.1 Bilateral damage to the thalamus abolishes waking consciousness. The critical site of this damage is believed to be a relatively small cluster of neurons, about the size of a pencil eraser on either side of the brain's midline, called the Intra-Laminar Nuclei (ILN) because they are located inside the white layers (laminae) that divide the two thalami into their major groupings of nuclei. The fact that bilateral damage to the ILNs abolishes consciousness is very unusual. There is no other (...) site in the brain that has this property, except the reticular formation in the brain stem. In contrast, huge chunks of cortex can be damaged without abolishing the STATE of consciousness. (Cortical damage does change the CONTENTS of consciousness, of course). (shrink)
Revonsuo argues that current brain imaging methods do not allow us to ‘discover’ consciousness. While all observational methods in science have limitations, consciousness is such a massive and pervasive phenomenon that we cannot fail to observe its effects at every level of brain organization: molecular, cellular, electrical, anatomical, metabolic, and even the ‘higher levels of electrophysiological organization that are crucial for the empirical discovery and theoretical explanation of consciousness’ . Indeed, the first major discovery in that respect was Hans Berger's (...) finding that scalp EEG is massively different between waking and deep sleep, already seven decades ago. We now have perhaps a dozen sophisticated methods for monitoring consciousness-related activity at multiple levels of brain observation. Theoretical progress has come quite rapidly. Recently, E.R. John and colleagues have made fundamental findings using Quantitative EEG, showing consistent brainwide changes as a result of several types of general anaesthetics . John has proposed a neuronal ‘field theory’ to account for those results. Another promising new method involves frequency-tagging of competing stimuli, allowing us to follow the activity of billions of neurons synchronized to particular conscious stimuli, always compared to very similar unconscious input . A fundamental theoretical account of such results has been provided by Tononi & Edelman . Such results and theory are in broad agreement with the cognitive theory proposed by Baars. (shrink)
The limited capacity of immediate memory “rides” on the even more limited capacity of consciousness, which reflects the dynamic activity of the thalamocortical core of the brain. Recent views of the conscious narrow-capacity component of the brain are explored with reference to global workspace theory (Baars 1988; 1993; 1998). The radical limits of immediate memory must be explained in terms of biocognitive brain architecture.
Can we make progress exploring consciousness? Or is it forever beyond human reach? In science we never know the ultimate outcome of the journey. We can only take whatever steps our current knowledge affords. This paper explores today's evidence from the viewpoint of Global Workspace theory. First, we ask what kind of evidence has the most direct bearing on the question. The answer given here is ‘contrastive analysis’ -- a set of paired comparisons between similar conscious and unconscious processes. This (...) body of evidence is already quite large, and constrains any possible theory . Because it involves both conscious and unconscious events, it deals directly with our own subjective experience, as anyone can tell by trying the demonstrations in this article. (shrink)
The standard behavioral index for human consciousness is the ability to report events with accuracy. While this method is routinely used for scientific and medical applications in humans, it is not easy to generalize to other species. Brain evidence may lend itself more easily to comparative testing. Human consciousness involves widespread, relatively fast low-amplitude interactions in the thalamocortical core of the brain, driven by current tasks and conditions. These features have also been found in other mammals, which suggests that consciousness (...) is a major biological adaptation in mammals. We suggest more than a dozen additional properties of human consciousness that may be used to test comparative predictions. Such homologies are necessarily more remote in non-mammals, which do not share the thalamocortical complex. However, as we learn more we may be able to make “deeper” predictions that apply to some birds, reptiles, large-brained invertebrates, and perhaps other species. (shrink)
Conscious perception, like the sight of a coffee cup, seems to involve the brain identifying a stimulus. But conscious input activates more brain regions than are needed to identify coffee cups and faces. It spreads beyond sensory cortex to frontoparietal association areas, which do not serve stimulus identiﬁcation as such. What is the role of those regions? Parietal cortex support the ‘ﬁrst person perspective’ on the visual world, unconsciously framing the visual object stream. Some prefrontal areas select and interpret conscious (...) events for executive control. Such functions can be viewed as properties of the subject, rather than the object, of experience – the ‘observing self’ that appears to be needed to maintain the conscious state. (shrink)
Most early studies of consciousness have focused on human subjects. This is understandable, given that humans are capable of reporting accurately the events they experience through language or by way of other kinds of voluntary response. As researchers turn their attention to other animals, “accurate report” methodologies become increasingly difficult to apply. Alternative strategies for amassing evidence for consciousness in non-human species include searching for evolutionary homologies in anatomical substrates and measurement of physiological correlates of conscious states. In addition, creative (...) means must be developed for eliciting behaviors consistent with consciousness. In this paper, we explore whether necessary conditions for consciousness can be established for species as disparate as birds and cephalopods. We conclude that a strong case can be made for avian species and that the case for cephalopods remains open. Nonetheless, a consistent effort should yield new means for interpreting animal behavior. (shrink)
In the last decade, careful studies of the living brain have opened the way for human consciousness to return to the heights it held before the behavioristic coup of 1913. This is illustrated by seven cases: the discovery of widespread brain activation during conscious perception; high levels of regional brain metabolism in the resting state of consciousness, dropping drastically in unconscious states; the brain correlates of inner speech; visual imagery; fringe consciousness; executive functions of the self; and volition. Other papers (...) in this issue expand on many of these points. . In the past, evidence based on subjective reports was often neglected . It is still true that brain evidence has greater credibility than subjective reports, no matter how reliable. What is new is increasing convergence between subjective experiences and brain observations. For that reason it is no longer rare to see the word 'consciousness' and 'subjectivity' in major science journals. No one so far has discovered a gulf dividing mind and brain. On the contrary, the new evidence supports the central role of consciousness as it was regarded over more than two millenia of written thought. In a sense this was predictable. Nature is full of unexpected convergences -- between fruit fly genes and the human body, between the arc of a tennis ball and the orbit of Mars, and between consciousness and the brain. These convergences show once again the remarkable unity of the observable universe. (shrink)
Neural Darwinism (ND) is a large scale selectionist theory of brain development and function that has been hypothesized to relate to consciousness. According to ND, consciousness is entailed by reentrant interactions among neuronal populations in the thalamocortical system (the ‘dynamic core’). These interactions, which permit high-order discriminations among possible core states, confer selective advantages on organisms possessing them by linking current perceptual events to a past history of value-dependent learning. Here, we assess the consistency of ND with 16 widely recognized (...) properties of consciousness, both physiological (for example, consciousness is associated with widespread, relatively fast, low amplitude interactions in the thalamocortical system), and phenomenal (for example, consciousness involves the existence of a private flow of events available only to the experiencing subject). While no theory accounts fully for all of these properties at present, we find that ND and its recent extensions fare well. (shrink)
When “divided attention” methods were discovered in the 1950s their implications for conscious experience were not widely appreciated. Yet when people process competing streams of sensory input they show both selective processesandclear contrasts between conscious and unconscious events. This paper suggests that the term “attention” may be best applied to theselection and maintenanceof conscious contents and distinguished from consciousness itself. This is consistent with common usage. The operational criteria for selective attention, defined in this way, are entirely different from those (...) used to assess consciousness. To illustrate the scientific usefulness of the distinction it is applied to Posner's brain model of visual attention. It seems that features that are often attributed to attention—like limited capacity—may more accurately be viewed as properties of consciousness. (shrink)
In humans, conscious perception and cognition depends upon the thalamocortical complex, which supports perception, explicit cognition, memory, language, planning, and strategic control. When parts of the T-C system are damaged or stimulated, corresponding effects are found on conscious contents and state, as assessed by reliable reports. In contrast, large regions like cerebellum and basal ganglia can be damaged without affecting conscious cognition directly. Functional brain recordings also show robust activity differences in cortex between experimentally matched conscious and unconscious events. This (...) basic anatomy and physiology is highly conserved in mammals and perhaps ancestral reptiles. While language is absent in other species, homologies in perception, memory, and motor cortex suggest that consciousness of one kind or another may be biologically fundamental and phylogenetically ancient. In humans we infer subjective experiences from behavioral and brain evidence. This evidence is quite similar in other mammals and perhaps some non-mammalian species. On the weight of the biological evidence, therefore, subjectivity may be conserved in species with human-like brains and behavior. (shrink)
When are psychologists entitled to call a certain theoretical construct "consciousness?" Over the past few decades cognitive psychologists have reintroduced almost the entire conceptual vocabulary of common sense psychology, but now in a way that is tied explicitly to reliable empirical observations, and to compelling and increasingly adequate theoretical models. Nevertheless, until the past few years most cognitive psychologists and neuroscientists avoided dealing with consciousness. Today there is an increasing willingness to do so. But is "consciousness" different from other theoretical (...) entities like "working memory" or "mental imagery"? Some argue that under no circumstances can empirical science speak of consciousness as such, while others claim that the scientific goal is "knowing what it is like to be a bat" --- to share an organism's conscious experience . The Bat Criterion is ominously reminiscent of the protracted debate on the consciousness of ants and amoebas that caused so much uneasiness in psychology around 1900. It seems to demand that we first solve the mind-body problem as a condition of doing sensible science, and thereby creates the risk of endless, fruitless controversy. The endless philosophical debate about consciousness helped trigger the Behaviorist revolution about 1913, which threw out the baby of consciousness with the bathwater of perennial, circular debate. We've been that way; let's not go back to it. This paper maintains that the position of behavioristic denial is far too restrictive, but that the Bat Criterion is far too demanding --- that in fact, we only need to specify comparable pairs of psychological phenomena that differ only in the fact that one member of any pair is conscious, while the other is not. This "method of contrastive analysis" is a generalization of the experimental method, with consciousness as a variable whose interaction with other psychological and biological phenomena can be assessed in standard ways. As usual in science, this strategy is pragmatic: If it appears to yield sensible results, it can be a stepping-stone toward further understanding . This paper describes five sets of well-established pairs of phenomena that meet these criteria. Others are presented elsewhere, with more of a theoretical interpretation . Here I simply want to show that any adequate theory of conscious experience must satisfy these demanding but achievable empirical constraints. (shrink)
Our aim in this reply is to defend Global Workspace theory (GWT) from the challenge of Block's article. We argue that Block's article relies on an outdated and imprecise concept of access, and perpetuates a common misunderstanding of GWT that conflates the global workspace with working memory. In the light of the relevant clarifications, Block's conclusion turns out to be unwarranted, and the basic tenets of GWT emerge unscathed.
B.F. Skinner was the voice of radical behaviourism for some five decades, fighting relentlessly against consciousness as a scientific question. While in public he always argued the case for behaviourism, in fact Skinner was deeply at odds with himself, as he reveals in several books. Surprisingly, as a college student he was deeply interested in becoming a stream-of-consciousness novelist. When that ambition failed, he reacted with a radical rejection of the conscious life. Decades later Skinner's inner struggle still continued, as (...) his autobiography shows. Like a mystery novelist, B.F. Skinner again and again provides the clues to his own secret. Skinner's conflict about consciousness was not just a personal idiosyncracy. Behaviourism and its radical rejection of personal experience was a major theme of the twentieth century, and continues even today. Rejection of consciousness became a core belief for academic psychologists and philosophers in the English-speaking world, justifying their claim to standing among the physical sciences. Skinner's life suggests that radical behaviourism may be associated with psychological conflict and some degree of dissociation. It also raises questions about the cultural climate that celebrated the rejection of consciousness. (shrink)
The world of our experience consists at all times of two parts, an objective and a subjective part . . . The objective part is the sum total of whatsoever at any given time we may be thinking of, the subjective part is the inner 'state' in which the thinking comes to pass.
?In everday language, the word ?attention? implies control of access to consciousness, and we adopt this usage here. Attention itself can be either voluntary or automatic. This can be readily modeled in the theory. Further, a contrastive analysis of spontaneously self?attributed vs. self?alien experiences suggests that ?self? can be interpreted as the more enduring, higher levels of the dominant context hierarchy, which create continuity over the changing flow of events. Since context is by definition unconscious in GW theory, self in (...) this sense is thought to be inherently unconscious as well. This proposal is consistent with a great deal of objective evidence. However, aspects of self may become known through ?conscious self-monitoring,? a process that ??is useful for self-evaluation and self?control. The results of conscious self-monitoring are combined with self?evaluation criteria, presumably of social origin, to produce a stable ?self?concept?, which functions as a supervisory system within the larger self organization. (shrink)
After suggesting an operational definition for fringe experiences—as opposed to clearly conscious and clearly unconscious phenomena—we examine three empirical cases: The tip-of-the-tongue experience, the fringe experience of "wrongness," and the case of conscious focus on abstract, hard-to-image conscious contents. In each case, Mangan′s four major claims are explored in some detail. Most tasks seem to involve a combination of conscious experiences, complex unconscious representations, and multiple fringe experiences. The chief disagreement from this analysis involves vague experiences that are generally believed (...) to be focal: The case of currently topical abstract concepts, which are not reported as conscious images or percepts. In the interest of caution, it may be better to speak of "conscious access" to focal abstract concepts, rather than "conscious experience" of such concepts. There may be other vague but focally conscious phenomena, such as an intention to act, the signal for executing a prepared action, and so on. Mangan′s points are generally supported, with some qualifications. (shrink)