Saskia Nagel | University of Twente (original) (raw)
Papers by Saskia Nagel
Theories of embodied cognition propose that perception is shaped by sensory stimuli and by the ac... more Theories of embodied cognition propose that perception is shaped by sensory stimuli and by the actions of the organism. Following sensorimotor contingency theory, the mastery of lawful relations between own behavior and resulting changes in sensory signals, called sensorimotor contingencies, is constitutive of conscious perception. Sensorimotor contingency theory predicts that, after training, knowledge relating to new sensorimotor contingencies develops, leading to changes in the activation of sensorimotor systems, and concomitant changes in perception. In the present study, we spell out this hypothesis in detail and investigate whether it is possible to learn new sensorimotor contingencies by sensory augmentation. Specifically, we designed an fMRI compatible sensory augmentation device, the feelSpace belt, which gives orientation information about the direction of magnetic north via vibrotactile stimulation on the waist of participants. In a longitudinal study, participants trained with this belt for seven weeks in natural environment. Our EEG results indicate that training with the belt leads to changes in sleep architecture early in the training phase, compatible with the consolidation of procedural learning as well as increased sensorimotor processing and motor programming. The fMRI results suggest that training entails activity in sensory as well as higher motor centers and brain areas known to be involved in navigation. These neural changes are accompanied with changes in how space and the belt signal are perceived, as well as with increased trust in navigational ability. Thus, our data on physiological processes and subjective experiences are compatible with the hypothesis that new sensorimotor contingencies can be acquired using sensory augmentation.
Encyclopedia of Global Bioethics, 2015
The American journal of bioethics : AJOB, 2015
Http Dx Doi Org 10 1080 21507740 2013 827278, Sep 11, 2013
Frontiers in Human Neuroscience, 2012
Common navigational aids used by blind travelers during large-scale navigation divert attention a... more Common navigational aids used by blind travelers during large-scale navigation divert attention away from important cues of the immediate environment (i.e., approaching vehicles). Sensory augmentation devices, relying on principles similar to those at work in sensory substitution, can potentially bypass the bottleneck of attention through sub-cognitive implementation of a set of rules coupling motor actions with sensory stimulation. We provide a late blind subject with a vibrotactile belt that continually signals the direction of magnetic north. The subject completed a set of behavioral tests before and after an extended training period. The tests were complemented by questionnaires and interviews. This newly supplied information improved performance on different time scales. In a pointing task we demonstrate an instant improvement of performance based on the signal provided by the device. Furthermore, the signal was helpful in relevant daily tasks, often complicated for the blind, such as keeping a direction over longer distances or taking shortcuts in familiar environments. A homing task with an additional attentional load demonstrated a significant improvement after training. The subject found the directional information highly expedient for the adjustment of his inner maps of familiar environments and describes an increase in his feeling of security when exploring unfamiliar environments with the belt.The results give evidence for a firm integration of the newly supplied signals into the behavior of this late blind subject with better navigational performance and more courageous behavior in unfamiliar environments. Most importantly, the complementary information provided by the belt lead to a positive emotional impact with enhanced feeling of security. The present experimental approach demonstrates the positive potential of sensory augmentation devices for the help of handicapped people.
The American Journal of Bioethics, 2012
Neurology, 2013
The use of prescription medication to augment cognitive or affective function in healthy personso... more The use of prescription medication to augment cognitive or affective function in healthy personsor neuroenhancement-is increasing in adult and pediatric populations. In children and adolescents, neuroenhancement appears to be increasing in parallel to the rising rates of attention-deficit disorder diagnoses and stimulant medication prescriptions, and the opportunities for medication diversion. Pediatric neuroenhancement remains a particularly unsettled and value-laden practice, often without appropriate goals or justification. Pediatric neuroenhancement presents its own ethical, social, legal, and developmental issues, including the fiduciary responsibility of physicians caring for children, the special integrity of the doctor-child-parent relationship, the vulnerability of children to various forms of coercion, distributive justice in school settings, and the moral obligation of physicians to prevent misuse of medication. Neurodevelopmental issues include the importance of evolving personal authenticity during childhood and adolescence, the emergence of individual decision-making capacities, and the
Expert Review of Neurotherapeutics, 2014
The prevalence of attention deficit hyperactivity disorder (ADHD) diagnoses is rising. ADHD is cl... more The prevalence of attention deficit hyperactivity disorder (ADHD) diagnoses is rising. ADHD is closely linked to its treatment with medications such as methylphenidate and amphetamines, which have popular appeal as neuroenhancement drugs by persons without a neurological disorder. The three main reasons for the increase in ADHD medication demand, production, and consumption are a) the inclusion of milder ADHD diagnoses; b) the vast marketing of ADHD medications by the pharmaceutical industry; and c) the illegal diversion of controlled ADHD medication to consumers seeking stimulants as neuroenhancements. Rapidly rising rates of any neurological disorder - especially a behaviorly-defined disorder closely linked to potent medications currently prescribed to more than 5% of the population - deserves ongoing scrutiny. Major social and ethical problems arise from vague-symptom medicalization, neurological disorder trivialization, medication overuse, and controlled substances diversion to healthy persons for nonmedical purposes. We argue against the 'spectrumization' of ADHD in an effort to curtail further diagnosis creep.
There is a remedy available for many of our ailments: Psychopharmacology promises to alleviate un... more There is a remedy available for many of our ailments: Psychopharmacology promises to alleviate unsatisfying memory, bad moods, and low self-esteem. Bioethicists have long discussed the ethical implications of enhancement interventions. However, they have not considered relevant evidence from psychology and economics. The growth in autonomy in many areas of life is publicized as progress for the individual. However, the
There is a need to diversify mental health research that uses brain imaging. Currently, this rese... more There is a need to diversify mental health research that uses brain imaging. Currently, this research almost exclusively includes participants from the 'Western' world, a majority of whom are Caucasian (Henrich et al, 2010a; 2010b). In light of studies from cultural neuroscience, which use brain imaging to demonstrate that people from different countries exhibit different neural activity, the lack of diversity in contemporary mental health research may pose a systematic bias of the data and interpretation. Considering that disorders are highly diverse between patients and across cultural groups, brain-based characteristics of disorders may vary across populations, making aberrant neural signatures difficult to identify if they exist at all. Further research could expand clinical understanding of diverse disorder phenotypes for globally shared disorders (e.g., schizophrenia) as well as generating new knowledge about culture-bound syndromes. This paper begins by demonstrating the underrepresentation of diverse populations in neuropsychiatry and then systematically discusses problems that increasing representation may solve, as well as research opportunities and implications for mental health practice, particularly for fields like transcultural psychiatry and global mental health.
Culture is part of an extensive feedback loop, which simultaneously influences and is influenced ... more Culture is part of an extensive feedback loop, which simultaneously influences and is influenced by many organismic levels including cultural context, neural events, and behavior, among others. Aside from behavioral variations, however, the influence cultural contexts have on the form and expression of psychiatric disorders has not been widely studied. Studying additional parts of this feedback loop, such as differences in neural processes, may yield new insights into these disorders. Recent studies in neuroscience show that culturally contingent social pressures shape some neural pathways but not others in non-patient participants. Presumably patient studies would reveal equally diverse findings. In which case, methodologies in the neurosciences potentially offer additional ways to assess the impact of culture on psychiatric health and symptomatology. However, implementing these methodologies raises important theoretical and ethical concerns, which must be resolved to maintain patient individuality and to acknowledge the complexity of cultural diversity. This paper discusses cultural context as a major influence on and byproduct of human neural plasticity and advocates a Culture-Brain-Behavior (CBB) interaction model for conceptualizing the relationship between culture, brain, and disorder. Recommendations are made for responsibly integrating neuroscientific techniques into transcultural psychiatric research by taking a systems approach to evaluating disorders.
Progress in Neuroscience advances rapidly and promises to change some of the basic concepts we ha... more Progress in Neuroscience advances rapidly and promises to change some of the basic concepts we have about ourselves. The field of Neuroethics is concerned with the resulting ethical implications. In this paper, we propose a framework to systematize the questions and positions in this context. We start with the discussion of three concrete cases around the topics of treatment/enhancement, personhood
Theories of embodied cognition propose that perception is shaped by sensory stimuli and by the ac... more Theories of embodied cognition propose that perception is shaped by sensory stimuli and by the actions of the organism. Following sensorimotor contingency theory, the mastery of lawful relations between own behavior and resulting changes in sensory signals, called sensorimotor contingencies, is constitutive of conscious perception. Sensorimotor contingency theory predicts that, after training, knowledge relating to new sensorimotor contingencies develops, leading to changes in the activation of sensorimotor systems, and concomitant changes in perception. In the present study, we spell out this hypothesis in detail and investigate whether it is possible to learn new sensorimotor contingencies by sensory augmentation. Specifically, we designed an fMRI compatible sensory augmentation device, the feelSpace belt, which gives orientation information about the direction of magnetic north via vibrotactile stimulation on the waist of participants. In a longitudinal study, participants trained with this belt for seven weeks in natural environment. Our EEG results indicate that training with the belt leads to changes in sleep architecture early in the training phase, compatible with the consolidation of procedural learning as well as increased sensorimotor processing and motor programming. The fMRI results suggest that training entails activity in sensory as well as higher motor centers and brain areas known to be involved in navigation. These neural changes are accompanied with changes in how space and the belt signal are perceived, as well as with increased trust in navigational ability. Thus, our data on physiological processes and subjective experiences are compatible with the hypothesis that new sensorimotor contingencies can be acquired using sensory augmentation.
Encyclopedia of Global Bioethics, 2015
The American journal of bioethics : AJOB, 2015
Http Dx Doi Org 10 1080 21507740 2013 827278, Sep 11, 2013
Frontiers in Human Neuroscience, 2012
Common navigational aids used by blind travelers during large-scale navigation divert attention a... more Common navigational aids used by blind travelers during large-scale navigation divert attention away from important cues of the immediate environment (i.e., approaching vehicles). Sensory augmentation devices, relying on principles similar to those at work in sensory substitution, can potentially bypass the bottleneck of attention through sub-cognitive implementation of a set of rules coupling motor actions with sensory stimulation. We provide a late blind subject with a vibrotactile belt that continually signals the direction of magnetic north. The subject completed a set of behavioral tests before and after an extended training period. The tests were complemented by questionnaires and interviews. This newly supplied information improved performance on different time scales. In a pointing task we demonstrate an instant improvement of performance based on the signal provided by the device. Furthermore, the signal was helpful in relevant daily tasks, often complicated for the blind, such as keeping a direction over longer distances or taking shortcuts in familiar environments. A homing task with an additional attentional load demonstrated a significant improvement after training. The subject found the directional information highly expedient for the adjustment of his inner maps of familiar environments and describes an increase in his feeling of security when exploring unfamiliar environments with the belt.The results give evidence for a firm integration of the newly supplied signals into the behavior of this late blind subject with better navigational performance and more courageous behavior in unfamiliar environments. Most importantly, the complementary information provided by the belt lead to a positive emotional impact with enhanced feeling of security. The present experimental approach demonstrates the positive potential of sensory augmentation devices for the help of handicapped people.
The American Journal of Bioethics, 2012
Neurology, 2013
The use of prescription medication to augment cognitive or affective function in healthy personso... more The use of prescription medication to augment cognitive or affective function in healthy personsor neuroenhancement-is increasing in adult and pediatric populations. In children and adolescents, neuroenhancement appears to be increasing in parallel to the rising rates of attention-deficit disorder diagnoses and stimulant medication prescriptions, and the opportunities for medication diversion. Pediatric neuroenhancement remains a particularly unsettled and value-laden practice, often without appropriate goals or justification. Pediatric neuroenhancement presents its own ethical, social, legal, and developmental issues, including the fiduciary responsibility of physicians caring for children, the special integrity of the doctor-child-parent relationship, the vulnerability of children to various forms of coercion, distributive justice in school settings, and the moral obligation of physicians to prevent misuse of medication. Neurodevelopmental issues include the importance of evolving personal authenticity during childhood and adolescence, the emergence of individual decision-making capacities, and the
Expert Review of Neurotherapeutics, 2014
The prevalence of attention deficit hyperactivity disorder (ADHD) diagnoses is rising. ADHD is cl... more The prevalence of attention deficit hyperactivity disorder (ADHD) diagnoses is rising. ADHD is closely linked to its treatment with medications such as methylphenidate and amphetamines, which have popular appeal as neuroenhancement drugs by persons without a neurological disorder. The three main reasons for the increase in ADHD medication demand, production, and consumption are a) the inclusion of milder ADHD diagnoses; b) the vast marketing of ADHD medications by the pharmaceutical industry; and c) the illegal diversion of controlled ADHD medication to consumers seeking stimulants as neuroenhancements. Rapidly rising rates of any neurological disorder - especially a behaviorly-defined disorder closely linked to potent medications currently prescribed to more than 5% of the population - deserves ongoing scrutiny. Major social and ethical problems arise from vague-symptom medicalization, neurological disorder trivialization, medication overuse, and controlled substances diversion to healthy persons for nonmedical purposes. We argue against the 'spectrumization' of ADHD in an effort to curtail further diagnosis creep.
There is a remedy available for many of our ailments: Psychopharmacology promises to alleviate un... more There is a remedy available for many of our ailments: Psychopharmacology promises to alleviate unsatisfying memory, bad moods, and low self-esteem. Bioethicists have long discussed the ethical implications of enhancement interventions. However, they have not considered relevant evidence from psychology and economics. The growth in autonomy in many areas of life is publicized as progress for the individual. However, the
There is a need to diversify mental health research that uses brain imaging. Currently, this rese... more There is a need to diversify mental health research that uses brain imaging. Currently, this research almost exclusively includes participants from the 'Western' world, a majority of whom are Caucasian (Henrich et al, 2010a; 2010b). In light of studies from cultural neuroscience, which use brain imaging to demonstrate that people from different countries exhibit different neural activity, the lack of diversity in contemporary mental health research may pose a systematic bias of the data and interpretation. Considering that disorders are highly diverse between patients and across cultural groups, brain-based characteristics of disorders may vary across populations, making aberrant neural signatures difficult to identify if they exist at all. Further research could expand clinical understanding of diverse disorder phenotypes for globally shared disorders (e.g., schizophrenia) as well as generating new knowledge about culture-bound syndromes. This paper begins by demonstrating the underrepresentation of diverse populations in neuropsychiatry and then systematically discusses problems that increasing representation may solve, as well as research opportunities and implications for mental health practice, particularly for fields like transcultural psychiatry and global mental health.
Culture is part of an extensive feedback loop, which simultaneously influences and is influenced ... more Culture is part of an extensive feedback loop, which simultaneously influences and is influenced by many organismic levels including cultural context, neural events, and behavior, among others. Aside from behavioral variations, however, the influence cultural contexts have on the form and expression of psychiatric disorders has not been widely studied. Studying additional parts of this feedback loop, such as differences in neural processes, may yield new insights into these disorders. Recent studies in neuroscience show that culturally contingent social pressures shape some neural pathways but not others in non-patient participants. Presumably patient studies would reveal equally diverse findings. In which case, methodologies in the neurosciences potentially offer additional ways to assess the impact of culture on psychiatric health and symptomatology. However, implementing these methodologies raises important theoretical and ethical concerns, which must be resolved to maintain patient individuality and to acknowledge the complexity of cultural diversity. This paper discusses cultural context as a major influence on and byproduct of human neural plasticity and advocates a Culture-Brain-Behavior (CBB) interaction model for conceptualizing the relationship between culture, brain, and disorder. Recommendations are made for responsibly integrating neuroscientific techniques into transcultural psychiatric research by taking a systems approach to evaluating disorders.
Progress in Neuroscience advances rapidly and promises to change some of the basic concepts we ha... more Progress in Neuroscience advances rapidly and promises to change some of the basic concepts we have about ourselves. The field of Neuroethics is concerned with the resulting ethical implications. In this paper, we propose a framework to systematize the questions and positions in this context. We start with the discussion of three concrete cases around the topics of treatment/enhancement, personhood