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Andreas Keil - One of the best experts on this subject based on the ideXlab platform.

  • oscillatory brain activity in the alpha range is modulated by the content of word prompted mental imagery
    Psychophysiology, 2015
    Co-Authors: Felix Bartsch, Gilava Hamuni, Vladimir Miskovic, P Lang, Andreas Keil
    Abstract:

    The Process of mental imagery has engaged the interest of philosophers and scientists for centuries (Waller, Schweitzer, Brunton & Knudson, 2012). Modern cognitive neuroscience approaches to this phenomenon suggest that mental imagery and perception share common neural real estate and entail similar functional Processes (e.g., Cichy, Heinzle, & Haynes, 2012; Kosslyn, 2005). Since mental imagery is, ipso facto, an internally oriented brain state, it is considerably more dependent on endogenous signaling in contrast to external perception, which involves a greater degree of bottom-up activation impinging via sensory Processes. Evidence from effective connectivity analyses indicates that visual imagery can be differentiated from visual perception by a reversal in the dominant direction of cortical information flow, with greater top-down signal flow to parieto-occipital cortical regions being observed during imagining than perceiving (Dentico et al., 2014). It is well known that in some contexts, imagery can interfere with perception (Craver-Lemley & Reeves, 1992) and that active inhibition of irrelevant sensory cortical regions may be observed during imagery to protect effortful Processing from interference (Amedi et al., 2005). Current theorizing about the role of large-scale brain activity reflected in the alpha band of the human electroencephalogram (EEG), suggests that these neuronal oscillations play an important role in active cortical inhibition and gating of information flow (e.g., Klimesch, 2006). Here, we aimed to characterize the changes in brain electrical activity induced by word-evoked mental imagery recorded from high-density EEG. In a series of experiments we manipulated the complexity of imagery content and contrasted verbally prompted imagery differing in the amount of affective arousal. As an active element of clinical intervention, imagery of emotional scenes is widely used in the treatment of fear, anxiety, depression, and many other diagnoses (Foa, McNally & Murdock, 1989; Kraft, 1970; Rubin, Spates, Johnson & Jouppi, 2009; Wiederhold, Jang, Gevirtz, Kim, Kim & Wiederhold, 2002). Much of this work has been guided by a bio-informational theory of imagery (Lang, 1979) which holds that verbal event descriptions of emotional situations activate a broad cognitive network in the brain, coding not just sensory information, but also associated semantic and efferent response representations. Subsequent research has shown, furthermore, that imagery word-cues engage facial, autonomic and somatic reflexes and that for emotionally arousing imagery these responses parallel reactions to actual pleasant or unpleasant events (Miller, Levin, Kozak, Cook, McLean & Lang, 1987). Hemodynamic neuroimaging research (e.g., functional magnetic resonance imaging, fMRI) provides further support for a network model, demonstrating that emotionally arousing imagery activates brain circuitry mediating fear/defensive and appetitive/reward responses. Arousing narratives prompt activation of supplementary Motor area and lateral cerebellum (Sabatinelli, Lang, Bradley & Flaisch, 2006), consistent with observations regarding reflex physiology. BOLD activation of the insula, amygdala, and frontal cortex is found for distressing imagery (Britton, Phan, Taylor, Fig & Liberzon, 2005; Sinha Lacadie, Skudlarski, Fulbright, Rounsaville, Kosten & Wexler, 2005), and Costa and collaborators (2010) reported that pleasant content selectively activated the nucleus accumbens and the ventral medial prefrontal cortex. While hemodynamic BOLD data have revealed much about metabolic changes in brain circuits active during imagery Processing, monitoring EEG oscillations during imagery episodes has the advantage of directly assessing neural activity from large populations of pyramidal cortical cells in real-time. The focus here is on variations in alpha amplitude (8–12 Hz), the human brain’s most evident large-scale oscillatory activity, visible prima vista in the raw EEG recordings (Berger, 1929, 1969). When participants are at rest, without engaging in active sensory Processing (for instance, with eyes closed), substantial oscillatory amplitude increases in the alpha-band are apparent (Berger, 1929; Pfurtscheller, Stancak & Neuper, 1996). This has sometimes been interpreted as evidence of an idling brain--alpha in this view being the signature of cortical tissue that neither receives nor Processes sensory input (Adrian & Matthews, 1934). Decreases in alpha spectral amplitude reliably occur with sensory Processing of external stimuli (Bollimunta, Mo, Schroeder & Ding, 2011; Keil, Mussweiler & Epstude, 2006; Ray & Cole, 1985), and the degree of reduction has been viewed as an inverse measure of cortical arousal (Aftanas, Reva, Varlamov, Pavlov & Makhnev, 2004; De Cesarei & Codispoti, 2011; Neuper, Grabner, Fink & Neubauer, 2005a). In a comprehensive review of the literature, Klimesch et al. (2006) reported that alpha increase is most often observed in tasks that involve top-down Processing in the absence of external stimulation, for instance when participants maintain an internal representation in working memory. According to this view the waxing and waning of alpha-band power might index decreased and increased receptivity of brain circuits to external inputs, creating temporal windows of excitability (Hanslmayr, Gross, Klimesch, & Shapiro, 2011). It has been suggested, furthermore, that regional alpha changes reflect cortically mediated “pulses” of inhibition that are flexibly deployed as determined by task demands (Foxe and Snyder, 2011; Jensen and Mazaheri, 2010; Mathewson, Lleras, Beck, Fabiani, Ro & Gratton, 2011). This alpha-band inhibition putatively performs an active gating function by channeling or facilitating the organization of different types of information Processing (Romei, Gross & Thut, 2010). In studies of spatial attention, spatial cues prompt fluctuations of alpha oscillations, such that alpha power is decreased in the hemisphere that is contralateral to the attended stimulus and increased in the ipsilateral hemisphere, implying that alpha-band oscillations optimize information Processing through the suppression of distracting information (see e.g., Worden, Foxe, Wang & Simpson, 2000). In line with this notion, parametric amplitude increases of alpha-range oscillations have been demonstrated in a variety of experimental designs that manipulate the degree of internally focused Processing, including Motor Process imagery (Neuper et al., 2005b; Pfurtscheller and Berghold, 1989), working memory load (Jensen, Gelfand, Kounios & Lisman, 2002; Klimesch, Sauseng & Hanslmayr, 2006), and music imagery (Schaefer, Vlek, & Desain, 2011). Summarizing this literature, the question arises as to whether mental imagery – a Process in which distracting information from external inputs may be actively suppressed to protect effortful Processing from harmful interference (e.g., Amedi et al., 2005) – prompts heightened alpha oscillations over widespread cortical areas. In the present research, participants were instructed to generate a mental image subsequent to linguistic cues. The brain’s time-varying oscillatory changes were measured with dense-array EEG. In consideration of previous findings regarding alpha enhancement in tasks involving internal Processing, three experiments addressed the following hypotheses: (1) in contrast to passive visual fixation, word prompted mental imagery should induce sustained alpha amplitude increases; (2) language-cued imagery should prompt greater alpha amplitude compared to imagery of semantically less-loaded, geometrical shapes in light of the increased demands on internal Processing loads in the former; and (3) emotionally arousing pleasant and unpleasant word-cues should occasion greater alpha amplitude than affective neutral word cues – potentially reflecting heightened working memory Processing, consequent on the broader cognitive/neural networks reported for emotional imagery (Lang, 1979).

Kuniyasu Imanaka - One of the best experts on this subject based on the ideXlab platform.

  • the involvement of cognitive Processing in a perceptual Motor Process examined with eeg time frequency analysis
    Clinical Neurophysiology, 2009
    Co-Authors: Hiromu Katsumata, Kunitake Suzuki, T Tanaka, Kuniyasu Imanaka
    Abstract:

    Abstract Objective For Motor activities, visual information is crucial for organizing a movement with respect to a given situation. The present study investigates how cognitive information Processing is associated with this visuoMotor Process. Methods Brain dynamics in executing two perceptual-Motor tasks were examined in terms of event-related synchronization (ERS) and event-related desynchronization (ERD) of EEG. Those tasks were (1) reaching toward and grasping a visual object with a pinch grip, and (2) matching the pinch grip size with respect to the perceived object size. Results According to the aperture size in the task execution, both the tasks were affected by the perceived object size inducing the Ebbinghaus illusion. The alpha-ERD patterns were associated with the movement execution and appeared to be identical in both the tasks, whilst the gamma-ERS appeared only for the grasping motion. Conclusions These results suggest that cognitive Processing was involved not only in the matching task but also in the grasping task. These ERD/ERS patterns are thought to reflect the similarity and difference in the perceptual-Motor Processes between the two tasks. Significance The analysis of ERD/ERS can provide insight on the qualitative feature in a visuoMotor Process associated with the involvement of cognitive Processing.

Felix Bartsch - One of the best experts on this subject based on the ideXlab platform.

  • oscillatory brain activity in the alpha range is modulated by the content of word prompted mental imagery
    Psychophysiology, 2015
    Co-Authors: Felix Bartsch, Gilava Hamuni, Vladimir Miskovic, P Lang, Andreas Keil
    Abstract:

    The Process of mental imagery has engaged the interest of philosophers and scientists for centuries (Waller, Schweitzer, Brunton & Knudson, 2012). Modern cognitive neuroscience approaches to this phenomenon suggest that mental imagery and perception share common neural real estate and entail similar functional Processes (e.g., Cichy, Heinzle, & Haynes, 2012; Kosslyn, 2005). Since mental imagery is, ipso facto, an internally oriented brain state, it is considerably more dependent on endogenous signaling in contrast to external perception, which involves a greater degree of bottom-up activation impinging via sensory Processes. Evidence from effective connectivity analyses indicates that visual imagery can be differentiated from visual perception by a reversal in the dominant direction of cortical information flow, with greater top-down signal flow to parieto-occipital cortical regions being observed during imagining than perceiving (Dentico et al., 2014). It is well known that in some contexts, imagery can interfere with perception (Craver-Lemley & Reeves, 1992) and that active inhibition of irrelevant sensory cortical regions may be observed during imagery to protect effortful Processing from interference (Amedi et al., 2005). Current theorizing about the role of large-scale brain activity reflected in the alpha band of the human electroencephalogram (EEG), suggests that these neuronal oscillations play an important role in active cortical inhibition and gating of information flow (e.g., Klimesch, 2006). Here, we aimed to characterize the changes in brain electrical activity induced by word-evoked mental imagery recorded from high-density EEG. In a series of experiments we manipulated the complexity of imagery content and contrasted verbally prompted imagery differing in the amount of affective arousal. As an active element of clinical intervention, imagery of emotional scenes is widely used in the treatment of fear, anxiety, depression, and many other diagnoses (Foa, McNally & Murdock, 1989; Kraft, 1970; Rubin, Spates, Johnson & Jouppi, 2009; Wiederhold, Jang, Gevirtz, Kim, Kim & Wiederhold, 2002). Much of this work has been guided by a bio-informational theory of imagery (Lang, 1979) which holds that verbal event descriptions of emotional situations activate a broad cognitive network in the brain, coding not just sensory information, but also associated semantic and efferent response representations. Subsequent research has shown, furthermore, that imagery word-cues engage facial, autonomic and somatic reflexes and that for emotionally arousing imagery these responses parallel reactions to actual pleasant or unpleasant events (Miller, Levin, Kozak, Cook, McLean & Lang, 1987). Hemodynamic neuroimaging research (e.g., functional magnetic resonance imaging, fMRI) provides further support for a network model, demonstrating that emotionally arousing imagery activates brain circuitry mediating fear/defensive and appetitive/reward responses. Arousing narratives prompt activation of supplementary Motor area and lateral cerebellum (Sabatinelli, Lang, Bradley & Flaisch, 2006), consistent with observations regarding reflex physiology. BOLD activation of the insula, amygdala, and frontal cortex is found for distressing imagery (Britton, Phan, Taylor, Fig & Liberzon, 2005; Sinha Lacadie, Skudlarski, Fulbright, Rounsaville, Kosten & Wexler, 2005), and Costa and collaborators (2010) reported that pleasant content selectively activated the nucleus accumbens and the ventral medial prefrontal cortex. While hemodynamic BOLD data have revealed much about metabolic changes in brain circuits active during imagery Processing, monitoring EEG oscillations during imagery episodes has the advantage of directly assessing neural activity from large populations of pyramidal cortical cells in real-time. The focus here is on variations in alpha amplitude (8–12 Hz), the human brain’s most evident large-scale oscillatory activity, visible prima vista in the raw EEG recordings (Berger, 1929, 1969). When participants are at rest, without engaging in active sensory Processing (for instance, with eyes closed), substantial oscillatory amplitude increases in the alpha-band are apparent (Berger, 1929; Pfurtscheller, Stancak & Neuper, 1996). This has sometimes been interpreted as evidence of an idling brain--alpha in this view being the signature of cortical tissue that neither receives nor Processes sensory input (Adrian & Matthews, 1934). Decreases in alpha spectral amplitude reliably occur with sensory Processing of external stimuli (Bollimunta, Mo, Schroeder & Ding, 2011; Keil, Mussweiler & Epstude, 2006; Ray & Cole, 1985), and the degree of reduction has been viewed as an inverse measure of cortical arousal (Aftanas, Reva, Varlamov, Pavlov & Makhnev, 2004; De Cesarei & Codispoti, 2011; Neuper, Grabner, Fink & Neubauer, 2005a). In a comprehensive review of the literature, Klimesch et al. (2006) reported that alpha increase is most often observed in tasks that involve top-down Processing in the absence of external stimulation, for instance when participants maintain an internal representation in working memory. According to this view the waxing and waning of alpha-band power might index decreased and increased receptivity of brain circuits to external inputs, creating temporal windows of excitability (Hanslmayr, Gross, Klimesch, & Shapiro, 2011). It has been suggested, furthermore, that regional alpha changes reflect cortically mediated “pulses” of inhibition that are flexibly deployed as determined by task demands (Foxe and Snyder, 2011; Jensen and Mazaheri, 2010; Mathewson, Lleras, Beck, Fabiani, Ro & Gratton, 2011). This alpha-band inhibition putatively performs an active gating function by channeling or facilitating the organization of different types of information Processing (Romei, Gross & Thut, 2010). In studies of spatial attention, spatial cues prompt fluctuations of alpha oscillations, such that alpha power is decreased in the hemisphere that is contralateral to the attended stimulus and increased in the ipsilateral hemisphere, implying that alpha-band oscillations optimize information Processing through the suppression of distracting information (see e.g., Worden, Foxe, Wang & Simpson, 2000). In line with this notion, parametric amplitude increases of alpha-range oscillations have been demonstrated in a variety of experimental designs that manipulate the degree of internally focused Processing, including Motor Process imagery (Neuper et al., 2005b; Pfurtscheller and Berghold, 1989), working memory load (Jensen, Gelfand, Kounios & Lisman, 2002; Klimesch, Sauseng & Hanslmayr, 2006), and music imagery (Schaefer, Vlek, & Desain, 2011). Summarizing this literature, the question arises as to whether mental imagery – a Process in which distracting information from external inputs may be actively suppressed to protect effortful Processing from harmful interference (e.g., Amedi et al., 2005) – prompts heightened alpha oscillations over widespread cortical areas. In the present research, participants were instructed to generate a mental image subsequent to linguistic cues. The brain’s time-varying oscillatory changes were measured with dense-array EEG. In consideration of previous findings regarding alpha enhancement in tasks involving internal Processing, three experiments addressed the following hypotheses: (1) in contrast to passive visual fixation, word prompted mental imagery should induce sustained alpha amplitude increases; (2) language-cued imagery should prompt greater alpha amplitude compared to imagery of semantically less-loaded, geometrical shapes in light of the increased demands on internal Processing loads in the former; and (3) emotionally arousing pleasant and unpleasant word-cues should occasion greater alpha amplitude than affective neutral word cues – potentially reflecting heightened working memory Processing, consequent on the broader cognitive/neural networks reported for emotional imagery (Lang, 1979).

Hiromu Katsumata - One of the best experts on this subject based on the ideXlab platform.

  • the involvement of cognitive Processing in a perceptual Motor Process examined with eeg time frequency analysis
    Clinical Neurophysiology, 2009
    Co-Authors: Hiromu Katsumata, Kunitake Suzuki, T Tanaka, Kuniyasu Imanaka
    Abstract:

    Abstract Objective For Motor activities, visual information is crucial for organizing a movement with respect to a given situation. The present study investigates how cognitive information Processing is associated with this visuoMotor Process. Methods Brain dynamics in executing two perceptual-Motor tasks were examined in terms of event-related synchronization (ERS) and event-related desynchronization (ERD) of EEG. Those tasks were (1) reaching toward and grasping a visual object with a pinch grip, and (2) matching the pinch grip size with respect to the perceived object size. Results According to the aperture size in the task execution, both the tasks were affected by the perceived object size inducing the Ebbinghaus illusion. The alpha-ERD patterns were associated with the movement execution and appeared to be identical in both the tasks, whilst the gamma-ERS appeared only for the grasping motion. Conclusions These results suggest that cognitive Processing was involved not only in the matching task but also in the grasping task. These ERD/ERS patterns are thought to reflect the similarity and difference in the perceptual-Motor Processes between the two tasks. Significance The analysis of ERD/ERS can provide insight on the qualitative feature in a visuoMotor Process associated with the involvement of cognitive Processing.

P Lang - One of the best experts on this subject based on the ideXlab platform.

  • oscillatory brain activity in the alpha range is modulated by the content of word prompted mental imagery
    Psychophysiology, 2015
    Co-Authors: Felix Bartsch, Gilava Hamuni, Vladimir Miskovic, P Lang, Andreas Keil
    Abstract:

    The Process of mental imagery has engaged the interest of philosophers and scientists for centuries (Waller, Schweitzer, Brunton & Knudson, 2012). Modern cognitive neuroscience approaches to this phenomenon suggest that mental imagery and perception share common neural real estate and entail similar functional Processes (e.g., Cichy, Heinzle, & Haynes, 2012; Kosslyn, 2005). Since mental imagery is, ipso facto, an internally oriented brain state, it is considerably more dependent on endogenous signaling in contrast to external perception, which involves a greater degree of bottom-up activation impinging via sensory Processes. Evidence from effective connectivity analyses indicates that visual imagery can be differentiated from visual perception by a reversal in the dominant direction of cortical information flow, with greater top-down signal flow to parieto-occipital cortical regions being observed during imagining than perceiving (Dentico et al., 2014). It is well known that in some contexts, imagery can interfere with perception (Craver-Lemley & Reeves, 1992) and that active inhibition of irrelevant sensory cortical regions may be observed during imagery to protect effortful Processing from interference (Amedi et al., 2005). Current theorizing about the role of large-scale brain activity reflected in the alpha band of the human electroencephalogram (EEG), suggests that these neuronal oscillations play an important role in active cortical inhibition and gating of information flow (e.g., Klimesch, 2006). Here, we aimed to characterize the changes in brain electrical activity induced by word-evoked mental imagery recorded from high-density EEG. In a series of experiments we manipulated the complexity of imagery content and contrasted verbally prompted imagery differing in the amount of affective arousal. As an active element of clinical intervention, imagery of emotional scenes is widely used in the treatment of fear, anxiety, depression, and many other diagnoses (Foa, McNally & Murdock, 1989; Kraft, 1970; Rubin, Spates, Johnson & Jouppi, 2009; Wiederhold, Jang, Gevirtz, Kim, Kim & Wiederhold, 2002). Much of this work has been guided by a bio-informational theory of imagery (Lang, 1979) which holds that verbal event descriptions of emotional situations activate a broad cognitive network in the brain, coding not just sensory information, but also associated semantic and efferent response representations. Subsequent research has shown, furthermore, that imagery word-cues engage facial, autonomic and somatic reflexes and that for emotionally arousing imagery these responses parallel reactions to actual pleasant or unpleasant events (Miller, Levin, Kozak, Cook, McLean & Lang, 1987). Hemodynamic neuroimaging research (e.g., functional magnetic resonance imaging, fMRI) provides further support for a network model, demonstrating that emotionally arousing imagery activates brain circuitry mediating fear/defensive and appetitive/reward responses. Arousing narratives prompt activation of supplementary Motor area and lateral cerebellum (Sabatinelli, Lang, Bradley & Flaisch, 2006), consistent with observations regarding reflex physiology. BOLD activation of the insula, amygdala, and frontal cortex is found for distressing imagery (Britton, Phan, Taylor, Fig & Liberzon, 2005; Sinha Lacadie, Skudlarski, Fulbright, Rounsaville, Kosten & Wexler, 2005), and Costa and collaborators (2010) reported that pleasant content selectively activated the nucleus accumbens and the ventral medial prefrontal cortex. While hemodynamic BOLD data have revealed much about metabolic changes in brain circuits active during imagery Processing, monitoring EEG oscillations during imagery episodes has the advantage of directly assessing neural activity from large populations of pyramidal cortical cells in real-time. The focus here is on variations in alpha amplitude (8–12 Hz), the human brain’s most evident large-scale oscillatory activity, visible prima vista in the raw EEG recordings (Berger, 1929, 1969). When participants are at rest, without engaging in active sensory Processing (for instance, with eyes closed), substantial oscillatory amplitude increases in the alpha-band are apparent (Berger, 1929; Pfurtscheller, Stancak & Neuper, 1996). This has sometimes been interpreted as evidence of an idling brain--alpha in this view being the signature of cortical tissue that neither receives nor Processes sensory input (Adrian & Matthews, 1934). Decreases in alpha spectral amplitude reliably occur with sensory Processing of external stimuli (Bollimunta, Mo, Schroeder & Ding, 2011; Keil, Mussweiler & Epstude, 2006; Ray & Cole, 1985), and the degree of reduction has been viewed as an inverse measure of cortical arousal (Aftanas, Reva, Varlamov, Pavlov & Makhnev, 2004; De Cesarei & Codispoti, 2011; Neuper, Grabner, Fink & Neubauer, 2005a). In a comprehensive review of the literature, Klimesch et al. (2006) reported that alpha increase is most often observed in tasks that involve top-down Processing in the absence of external stimulation, for instance when participants maintain an internal representation in working memory. According to this view the waxing and waning of alpha-band power might index decreased and increased receptivity of brain circuits to external inputs, creating temporal windows of excitability (Hanslmayr, Gross, Klimesch, & Shapiro, 2011). It has been suggested, furthermore, that regional alpha changes reflect cortically mediated “pulses” of inhibition that are flexibly deployed as determined by task demands (Foxe and Snyder, 2011; Jensen and Mazaheri, 2010; Mathewson, Lleras, Beck, Fabiani, Ro & Gratton, 2011). This alpha-band inhibition putatively performs an active gating function by channeling or facilitating the organization of different types of information Processing (Romei, Gross & Thut, 2010). In studies of spatial attention, spatial cues prompt fluctuations of alpha oscillations, such that alpha power is decreased in the hemisphere that is contralateral to the attended stimulus and increased in the ipsilateral hemisphere, implying that alpha-band oscillations optimize information Processing through the suppression of distracting information (see e.g., Worden, Foxe, Wang & Simpson, 2000). In line with this notion, parametric amplitude increases of alpha-range oscillations have been demonstrated in a variety of experimental designs that manipulate the degree of internally focused Processing, including Motor Process imagery (Neuper et al., 2005b; Pfurtscheller and Berghold, 1989), working memory load (Jensen, Gelfand, Kounios & Lisman, 2002; Klimesch, Sauseng & Hanslmayr, 2006), and music imagery (Schaefer, Vlek, & Desain, 2011). Summarizing this literature, the question arises as to whether mental imagery – a Process in which distracting information from external inputs may be actively suppressed to protect effortful Processing from harmful interference (e.g., Amedi et al., 2005) – prompts heightened alpha oscillations over widespread cortical areas. In the present research, participants were instructed to generate a mental image subsequent to linguistic cues. The brain’s time-varying oscillatory changes were measured with dense-array EEG. In consideration of previous findings regarding alpha enhancement in tasks involving internal Processing, three experiments addressed the following hypotheses: (1) in contrast to passive visual fixation, word prompted mental imagery should induce sustained alpha amplitude increases; (2) language-cued imagery should prompt greater alpha amplitude compared to imagery of semantically less-loaded, geometrical shapes in light of the increased demands on internal Processing loads in the former; and (3) emotionally arousing pleasant and unpleasant word-cues should occasion greater alpha amplitude than affective neutral word cues – potentially reflecting heightened working memory Processing, consequent on the broader cognitive/neural networks reported for emotional imagery (Lang, 1979).