The method of positron emission tomography illustrates the circular logic popular in subtractive neuroimaging and linear reductive cognitive psychology. Both require that strictly feed-forward, modular, cognitive components exist, before the fact, to justify the inference of particular components from images after the fact. Also, both require a "true" componential theory of cognition and laboratory tasks, before the fact, to guarantee reliable choices for subtractive contrasts. None of these possibilities are likely. Consequently, linear reductive analysis has failed to yield general, (...) reliable, componential accounts. (shrink)

The method of positron emission tomography (PET imaging) illustrates the circular logic popular in subtractive neuroimaging and linear reductive cognitive psychology. Both require that strictly feed-forward, modular, cognitive components exist, before the fact, to justify the inference of particular components from images (or other observables) after the fact. Also, both require a "true" componential theory of cognition and laboratory tasks, before the fact, to guarantee reliable choices for subtractive contrasts. None of these possibilities are likely. Consequently, linear reductive analysis (...) has failed to yield general, reliable, componential accounts. (shrink)

The method of positron emission tomography illustrates the circular logic popular in subtractive neuroimaging and linear reductive cognitive psychology. Both require that strictly feed-forward, modular, cognitive components exist, before the fact, to justify the inference of particular components from images after the fact. Also, both require a "true" componential theory of cognition and laboratory tasks, before the fact, to guarantee reliable choices for subtractive contrasts. None of these possibilities are likely. Consequently, linear reductive analysis has failed to yield general, (...) reliable, componential accounts. (shrink)

Recent studies using functional magnetic resonance imaging of patients in a vegetative state have raised the possibility that such patients retain some degree of consciousness. In this paper, the ethical implications of such findings are outlined, in particular in relation to decisions about withdrawing life-sustaining treatment. It is sometimes assumed that if there is evidence of consciousness, treatment should not be withdrawn. But, paradoxically, the discovery of consciousness in very severely brain-damaged patients may provide more reason to let them (...) die. Although functional neuroimaging is likely to play an increasing role in the assessment of patients in a vegetative state, caution is needed in the interpretation of neuroimaging findings. (shrink)

The method of positron emission tomography illustrates the circular logic popular in subtractive neuroimaging and linear reductive cognitive psychology. Both require that strictly feed-forward, modular, cognitive components exist, before the fact, to justify the inference of particular components from images after the fact. Also, both require a "true" componential theory of cognition and laboratory tasks, before the fact, to guarantee reliable choices for subtractive contrasts. None of these possibilities are likely. Consequently, linear reductive analysis has failed to yield general, (...) reliable, componential accounts. (shrink)

Neuroscientists have long sought to study the dynamic activity of the human brain—what's happening in the brain, that is, while people are thinking, feeling, and acting. Ideally, an inside look at brain function would simultaneously and continuously measure the biochemical state of every cell in the central nervous system. While such a miraculous method is science fiction, a century of progress in neuroimaging technologies has made such simultaneous and continuous measurement a plausible fiction. Despite this progress, practitioners of modern (...) neuroimaging struggle with two kinds of limitations: those that attend the particular neuroimaging methods we have today and those that would limit any method of imaging neural activity, no matter how powerful.In this essay, I consider the liabilities and potential of techniques that measure human brain activity. I am concerned here only with methods that measure relevant physiologic states of the central nervous system and relate those measures to particular mental states. I will consider in particular the preeminent method of functional neuroimaging: BOLD fMRI. While there are several practical limits on the biological information that current technologies can measure, these limits—as important as they are—are minor in comparison to the fundamental logical restraints on the conclusions that can be drawn from brain imaging studies. (shrink)

Under the umbrella of the burgeoning neurotransdisciplines, scholars are using the principles and research methodologies of their primary and secondary fields to examine developments in neuroimaging, neuromodulation and psychopharmacology. The path for advanced scholarship at the intersection of law and neuroscience may clear if work across the disciplines is collected and reviewed and outstanding and debated issues are identified and clarified. In this article, I organize, examine and refine a narrow class of the burgeoning neurotransdiscipline scholarship; that is, scholarship (...) at the interface of law and functional magnetic resonance imaging (fMRI). (shrink)

Cowan argues that the true short-term memory (STM) capacity limit is about 4 items. Functional neuroimaging data converge with this conclusion, indicating distinct neural activity patterns depending on whether or not memory task-demands exceed this limit. STM for verbal information within that capacity invokes focal prefrontal cortical activation that increases with memory load. STM for verbal information exceeding that capacity invokes widespread prefrontal activation in regions associated with executive and attentional processes that may mediate chunking processes to accommodate (...) STM capacity limits. (shrink)

The neuroscientific investigation of sex differences has an unsavoury past, in which scientific claims reinforced and legitimated gender roles in ways that were not scientifically justified. Feminist critics have recently argued that the current use of functional neuroimaging technology in sex differences research largely follows that tradition. These charges of ‘neurosexism’ have been countered with arguments that the research being done is informative and valuable and that an over-emphasis on the perils, rather than the promise, of such research (...) threatens to hinder scientific progress. To investigate the validity of these contrasting concerns, recent functional magnetic resonance imaging (fMRI) investigations of sex differences and citation practices were systematically examined. In line with the notion of neurosexism, the research was found to support the influence of false-positive claims of sex differences in the brain, to enable the proliferation of untested, stereotype-consistent functional interpretations, and to pay insufficient attention to the potential plasticity of sex differences in both brain and mind. This, it is argued, creates a literature biased toward the presentation of sex differences in the brain as extensive, functionally significant, and fixed—and therefore implicitly supportive of a gender essentialist perspective. It is suggested that taking feminist criticisms into account would bring about substantial improvement in the quality of the science, as well as a reduction in socially harmful consequences. (shrink)

The subtraction and covariance paradigms are two analytic techniques used with functional neuroimaging data. The first assumes that a brain region participating in a task should show altered neural activity (relative to a control task). The second assumes that tasks are mediated by networks of interacting regions.Images of mindattempts to link results from the subtraction paradigm with a network interpretation that could have been more explicitly done using the covariance paradigm.

In their paper "Conceptual Challenges in the Neuroimaging of Psychiatric Disorders," Kanaan and McGuire (2011) review a number of methodological and analytical obstacles associated with the use of functional magnetic resonance imaging (fMRI) to study psychiatric disorders. Although we agree that there are challenges and limitations to this end, it would be a shame for those without a background in neuroimaging to walk away from this article with the impression that such work is too daunting, and thus (...) not worth pursuing. On the contrary, despite a number of challenges (which are an inevitable part of all research), fMRI has already contributed many important insights into the nature and mechanisms of .. (shrink)

The new field of neuroethics has recently emerged following unprecedented developments in the neurosciences. Neuroimaging and cognitive enhancement in particular are demanding ethical debate. For example, neuroscientists are able to measure, with increasing accuracy, intimate personal biases and thoughts as they occur in the brain. Smart drugs are now available that can effectively and safely enhance mental functioning in both healthy and clinical populations. This article describes the scientific principles behind these technologies, and urges the development of ethical principles (...) based on a clear understanding of them. Europe should take the United States’ lead in devoting resources specifically intended to examine neuroethical concerns within European healthcare and legal frameworks. (shrink)

Of the many futuristic prospects offered by neuroscience, one of the more controversial is ‘brain reading’: the use of functional neuroimaging to gain information about subjects’ mental states or thoughts. This technology has various possible applications, including ‘neuromarketing’ and lie detection. Would such applications violate subjects’ privacy rights? Conversely, if God knows and judges all our secret thoughts, do Christians have any stake in defending a right to mental privacy? This article argues that God’s knowledge of us is (...) different not only in degree but in kind from the knowledge sought through brain reading. This view of divine knowledge supports a theological account of privacy, richer and broader in scope than standard accounts of privacy rights, which can aid the ethical analysis of the use of brain reading technology for purposes such as marketing and lie detection. (shrink)

Of the many futuristic prospects offered by neuroscience, one of the more controversial is ‘brain reading’: the use of functional neuroimaging to gain information about subjects’ mental states or thoughts. This technology has various possible applications, including ‘neuromarketing’ and lie detection. Would such applications violate subjects’ privacy rights? Conversely, if God knows and judges all our secret thoughts, do Christians have any stake in defending a right to mental privacy? This article argues that God’s knowledge of us is (...) different not only in degree but in kind from the knowledge sought through brain reading. This view of divine knowledge supports a theological account of privacy, richer and broader in scope than standard accounts of privacy rights, which can aid the ethical analysis of the use of brain reading technology for purposes such as marketing and lie detection. (shrink)

The dominant model for interpreting brain imaging experiments assumes that the brain is organized to support mental processes that control behavior. However functional neuroimaging experiments, particularly of cognitive tasks, have not shown a high level of reproducibility and localization. This lack of clear functional segregation has been blamed on limitations in imaging technology and non linearity and regional overlap in how the brain implements these processes. However the validity of the underlying cognitive models used to describe the (...) brain have rarely been questioned or directly tested against imaging results. We propose an alternative model of brain function which correlates observed human behavior directly with measured brain activity without assumptions about intervening cognitive processes, that we term the Non-Cognitive Behavioral Model (NBM). Our model derives from Behavioral Psychology but is extended to include brain activations in addition to behavior as an observable. A further extension is the role of neuroplasticity as opposed to innate cognitive processes in the development of the brains support of cognitive behavior. Applications of NBM to neuroimaging studies are described and contrasted with the standard methodology which we refer to as the Standard Cognitive Model (SCM). In one application, the NBM correctly predicted the global, total energy consumption as the brain parameter that best correlates with a person being in the state of consciousness, a correlation missed by studies using the SCM due to its assumption that global activity does not support cognitive processes. Neuroplasticity is shown to provide a natural explanation of findings that object recognition activating the fusiform facial area comes from expertise through raining as opposed to the SCM explanation of an innate cognitive process specialized for face recognition. The conclusions are generalized to explain the poor reproducibility of cognitive processes reported in functional neuroimaging and to suggest how such studies can be used to better explain how the brain supports behavior. (shrink)

Feminist scholars have shown that research on sex/gender differences in the brain is often used to support gender stereotypes. Scientists use a variety of methodological and interpretive strategies to make their results consistent with these stereotypes. In this paper, I analyze functional magnetic resonance imaging (fMRI) research that examines differences between women and men in brain activity associated with emotion and show that these researchers go to great lengths to make their results consistent with the view that women are (...) more emotional than men. (shrink)

For more than a century the paradigm inspiringcognitive neuroscience has been modular and localist.Contemporary research in functional brain imaginggenerally relies on methods favorable to localizingparticular functions in one or more specific brainregions. Meanwhile, connectionist cognitive scientistshave celebrated the computational powers ofdistributed processing, and pioneered methods forinterpreting distributed representations. This papertakes a connectionist approach to functionalneuroimaging. A tabulation of 35 PET (positronemission tomography) experiments strongly indicatesdistributed function for at least the ''medium sized''anatomical units, the cortical Brodmann areas. Moreimportant, when these (...) PET experiments were interpretedas distributed representations, multidimensionalscaling revealed a ''brain activation space'' with asalient structure organized primarily by the sensorymodality of the stimulus, and secondarily by the typeof motor response. These results suggest that currentanalytical techniques in functional neuroimagingshould be augmented by distributed processinganalyses, and that these analyses may lead to manydiscoveries about the structure of ''inner space.''. (shrink)

Since the mid‐1980s, psychologists and neuroscientists have used brain imaging to test hypotheses about human thought processes and their neural instantiation. In just three decades, functional neuroimaging has been transformed from a crude clinical tool to a widely used research method for understanding the human brain and mind. Such rapidly achieved success is bound to evoke skepticism. A degree of skepticism toward new methods and ideas is both inevitable and useful in any field. It is especially valuable in (...) a science as young as cognitive neuroscience and its even younger siblings, social and affective neuroscience. Healthy skepticism encourages us to check our assumptions, recognize the limitations of our methods, and proceed thoughtfully. Skepticism itself, however, also must be examined.In this article, I review the most commonly voiced criticisms of functional neuroimaging. In the spirit of healthy skepticism, I will critically examine these criticisms themselves. Each contains at least a kernel of truth, although I will argue that in some cases the kernel has been overextended in ways that are inaccurate or misleading. (shrink)

:Recent neuroimaging research on disorders of consciousness provides direct evidence of covert consciousness otherwise not detected clinically in a subset of severely brain-injured patients. These findings have motivated strategic development of binary communication paradigms, from which researchers interpret voluntary modulations in brain activity to glean information about patients’ residual cognitive functions and emotions. The discovery of such responsiveness raises ethical and legal issues concerning the exercise of autonomy and capacity for decisionmaking on matters such as healthcare, involvement in research, (...) and end of life. These advances have generated demands for access to the technology against a complex background of continued scientific advancement, questions about just allocation of healthcare resources, and unresolved legal issues. Interviews with professionals whose work is relevant to patients with disorders of consciousness reveal priorities concerning further basic research, legal and policy issues, and clinical considerations. (shrink)

Sexual motivation is a fundamental behavior in human. For a long time, this behavior has been somehow ignored from psychological and neuroscientific research. In this article - reflecting the collaboration of a clinical psychologist and a neuroscientist - we show that in the current period, sexual affiliation is one of the most promising affiliation context to articulate a debate, a dialog and convergence points between psychoanalysis and neuroscience. Recent data on healthy sexual behavior and its compulsive variant are discussed under (...) the prism of neuroscience and psychoanalysis. Keywords: brain; fMRI; sexual affiliation (Published: 20 January 2012) Citation: Socioaffective Neuroscience & Psychology 2012, 2 : 11814 - DOI: 10.3402/snp.v2i0.11814. (shrink)

Objective: To examine how research ethics boards review research projects in emerging disciplines such as functional neuroimaging.Design: To compare the criteria applied and the decisions reached by REBs that reviewed the same mock research protocol in functional neuroimaging.Participants: 44 Canadian biomedical REBs, mostly working in public university or hospital settings.Main measurements: The mock research protocol “The Neurobiology of Social Behavior” included several ethical issues operating at all three levels: personal, institutional and social. Data consisting of responses (...) to closed questions were analysed quantitatively. Qualitative analysis of open-question responses used mixed classification.Results: Similar criteria were used by most participating REBs. Yet the project was unconditionally approved by 3 REBs, approved conditionally by 10 and rejected by 30.Conclusions: The results point to the difficulty for REBs of reviewing all kinds of research projects, regardless of field, by relying on international and national norms framed in general terms and a possible variation between REBs in the interpretation of their mandate for the protection of research subjects. (shrink)

In this chapter, we aimed at further characterizing the functional neuroanatomy of the human rapid eye movement (REM) sleep at the population level. We carried out a meta-analysis of a large dataset of positron emission tomography (PET) scans acquired during wakefulness, slow wave sleep and REM sleep, and focused especially on the brain areas in which the activity diminishes during REM sleep. Results show that quiescent regions are confined to the inferior and middle frontal cortex and to the inferior (...) parietal lobule. Providing a plausible explanation for some of the features of dream reports, these findings may help in refining the concepts, which try to account for human cognition during REM sleep. In particular, we discuss the significance of these results to explain the alteration in executive processes, episodic memory retrieval and self representation during REM sleep dreaming as well as the incorporation of external stimuli into the dream narrative. (shrink)

The pipeline framework for identifying ethical issues in machine learning healthcare applications outlined by Char et al. is a very useful starting point for the systematic consideration...

Money is a specifically human incentive. However, functional imaging techniques bring striking evidence that neural circuits pertaining to more “natural” addictive and rewarding processes are involved in response to monetary reward. Main results are evoked here, with specific brain responses demonstrated along the different stages of the process. (Published Online April 5 2006).