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Order-driven effects in auditory evoked potentials: First-impression prediction bias or adaptation?
20
IOP 2016
(iii) modulations of neural gain can explain the observed sustained field dynamics. To model these effects in terms of the underlying neurophysiology, we used DCM for cross-spectral density. We found evidence - in terms of effects of predictability on high-frequency gamma activity and the underlying neurophysiological mechanisms inferred from DCM that the slow-fluctuating changes in synaptic efficacy combined with sustained input (e.g. tone sequences) can result in large sustained effects on neural activity. doi:10.1016/j.ijpsycho.2016.07.065
370 Order-driven effects in auditory evoked potentials: First-impression prediction bias or adaptation? Juanita Todda, Daniel Mullensa, Andrew Heathcoteb, Lisa Sawyera, Alexander Provosta, Istvan Winklerc a University of Newcastle, Newcastle, Australia b University of TAS, Hobart, Australia c Research Centre for Natural Sciences, MTA, Institute of Cognitive Neuroscience and Psychology, Budapest, Hungary Background: Auditory evoked potentials (AEPs) can be used to study the formation and updating of internal models that predict the most likely “next state” of sensory activation based upon a history of patterning in sound. We test the hypothesis that a long-lasting firstimpression bias model-updating impacts (learning rates). Methods: Participants (n=40, 18-40yrs) heard tone sequences arranged in blocks such that one sound was common (standard=p=0.875) and the other rare (deviant=p=0.125). The two tones, presented binaurally at 300ms intervals, differed either in frequency (1000Hz/1200Hz) or duration (30ms/60ms). Four blocks (480 tones, each) with reversed tone probabilities alternated in separate sequences (i.e., ABAB). Three sequences were delivered: order1=ABAB, order 2=BABA and order3=ABAB. AEP amplitudes to standards and deviants were measured at “model-establishment” ranges in the sequence (the first 240 trials of each block) to index response “suppression” and prediction-error, respectively. Results & Discussion: AEP amplitude was order-dependent for both frequency and duration conditions. Deviant AEPs were largest when the sound was the first-deviant (larger in A-blocks of order 1 & 3 than A-blocks of order 2, and larger in B-blocks of order 2 than in B-Blocks of order 1 & 3). Remarkably, the AEP to standards was more suppressed if it had first been heard as a deviant in the sequence (more suppressed in B-blocks of order 1 & 3 than B-blocks of order 2, and more suppressed in A-blocks of order 2 than in A-Blocks of order 1 & 3). These tone-by-order interactions are consistent with the notion of a first-impression that biases learning rates – specifically, faster updating of internal models for sounds first heard as a rare deviant eliciting a prediction-error signal. doi:10.1016/j.ijpsycho.2016.07.066
133 Stimulus-specific adaptation in the auditory brain: A neuronal correlate for MMN? Manuel S. Malmierca Auditory Neuroscience Laboratory, Institute of Neuroscience of Castilla y León, University of Salamanca, Salamanca, Spain
Department of Cell Biology and Pathology, Faculty of Medicine, University of Salamanca, Campus Miguel de Unamuno, 37007, Salamanca, Spain Salamanca Institute for Biomedical Research, Salamanca, Spain Recent evidence suggests that we can hear an orderly acoustic stream organised according to sources and auditory objects, allowing us to distinguish deviant or novel events and select some sources or objects for further processing. Moreover, these perceptual achievements begins to be encoded at earliest stages of the auditory pathway. Stimulus-specific adaptation (SSA) is the reduction in the responses to a common sound relative to the same sound when rare. It was originally described in the primary auditory cortex (A1) as the neuronal correlate of the mismatch negativity (MMN), an important component of the auditory event-related potentials that is elicited by changes in the auditory environment. However, the relationship between SSA and the MMN is still a subject of debate. The MMN is a mid-late potential (~ 150-200 ms in humans), and its neural sources have been located mainly within non-primary auditory cortex in humans and animal models. Moreover, SSA is also present as early as in the auditory midbrain and thalamus (IC and MGB). In this talk I will show our recent findings on recordings from single neurons in the IC, MGB and auditory cortex (AC) of anaesthetized rats to an oddball paradigm similar to that used for MMN studies. Our data demonstrate that: 1) Most neurons in the non-lemnical divisions of the IC and MGB show strong SSA; 2) the magnitude of adaptation in many IC neurons increased proportionally with frequency contrast and low probability of occurrence for deviant tones. 3) SSA varies within the neuronal receptive field. 4) GABAergic and/or glycinergic inhibition play a role in shaping SSA in the IC and MGB. 5) Acetylcholine modulates SSA by differently affecting the response to the standard sounds. And, finally, 6) our most recent recordings from different AC fields demonstrate that SSA is much stronger and develops faster in non-primary than in primary auditory cortex, paralleling the organization of subcortical SSA.Taken together our results suggest that SSA can be generated in a bottom-up manner throughout the auditory pathway and they are congruent with the notion that subcortical SSA can contribute upstream to the generation of MMN. doi:10.1016/j.ijpsycho.2016.07.067
433 Event-related potential research on prediction and attention revisited under the predictive coding umbrella Erich Schröger Leipzig University, Leipzig, Germany Event-related potential (ERP) research from various fields (e.g. Mismatch negativity, N1 suppression) revealed an interesting pattern of modulations of ERPs elicited by predictable and by unpredictable sounds: Unpredictable sounds such as sounds occurring after a long silent inter-sound interval or sounds violating an established regularity are known to elicit enhanced brain responses (e.g. the N1), while predictable sounds such as sounds occurring after several repetitions of the same sound or self-generated sounds often elicit attenuated brain responses (e.g. the N1). This pattern of results can be explained with the predictive coding theory stating that our brain processes sensory input with respect to predictions derived from a neural model representing what we (implicitly or explicitly) believe being the cause of the sensory input. It is suggested that for each arriving sound, the prediction error (PE) is computed as the difference between the top-down prediction (P) and the sensory input (I), and sent as a feedforward signal to higher
IOP 2016
(iii) modulations of neural gain can explain the observed sustained field dynamics. To model these effects in terms of the underlying neurophysiology, we used DCM for cross-spectral density. We found evidence - in terms of effects of predictability on high-frequency gamma activity and the underlying neurophysiological mechanisms inferred from DCM that the slow-fluctuating changes in synaptic efficacy combined with sustained input (e.g. tone sequences) can result in large sustained effects on neural activity. doi:10.1016/j.ijpsycho.2016.07.065
370 Order-driven effects in auditory evoked potentials: First-impression prediction bias or adaptation? Juanita Todda, Daniel Mullensa, Andrew Heathcoteb, Lisa Sawyera, Alexander Provosta, Istvan Winklerc a University of Newcastle, Newcastle, Australia b University of TAS, Hobart, Australia c Research Centre for Natural Sciences, MTA, Institute of Cognitive Neuroscience and Psychology, Budapest, Hungary Background: Auditory evoked potentials (AEPs) can be used to study the formation and updating of internal models that predict the most likely “next state” of sensory activation based upon a history of patterning in sound. We test the hypothesis that a long-lasting firstimpression bias model-updating impacts (learning rates). Methods: Participants (n=40, 18-40yrs) heard tone sequences arranged in blocks such that one sound was common (standard=p=0.875) and the other rare (deviant=p=0.125). The two tones, presented binaurally at 300ms intervals, differed either in frequency (1000Hz/1200Hz) or duration (30ms/60ms). Four blocks (480 tones, each) with reversed tone probabilities alternated in separate sequences (i.e., ABAB). Three sequences were delivered: order1=ABAB, order 2=BABA and order3=ABAB. AEP amplitudes to standards and deviants were measured at “model-establishment” ranges in the sequence (the first 240 trials of each block) to index response “suppression” and prediction-error, respectively. Results & Discussion: AEP amplitude was order-dependent for both frequency and duration conditions. Deviant AEPs were largest when the sound was the first-deviant (larger in A-blocks of order 1 & 3 than A-blocks of order 2, and larger in B-blocks of order 2 than in B-Blocks of order 1 & 3). Remarkably, the AEP to standards was more suppressed if it had first been heard as a deviant in the sequence (more suppressed in B-blocks of order 1 & 3 than B-blocks of order 2, and more suppressed in A-blocks of order 2 than in A-Blocks of order 1 & 3). These tone-by-order interactions are consistent with the notion of a first-impression that biases learning rates – specifically, faster updating of internal models for sounds first heard as a rare deviant eliciting a prediction-error signal. doi:10.1016/j.ijpsycho.2016.07.066
133 Stimulus-specific adaptation in the auditory brain: A neuronal correlate for MMN? Manuel S. Malmierca Auditory Neuroscience Laboratory, Institute of Neuroscience of Castilla y León, University of Salamanca, Salamanca, Spain
Department of Cell Biology and Pathology, Faculty of Medicine, University of Salamanca, Campus Miguel de Unamuno, 37007, Salamanca, Spain Salamanca Institute for Biomedical Research, Salamanca, Spain Recent evidence suggests that we can hear an orderly acoustic stream organised according to sources and auditory objects, allowing us to distinguish deviant or novel events and select some sources or objects for further processing. Moreover, these perceptual achievements begins to be encoded at earliest stages of the auditory pathway. Stimulus-specific adaptation (SSA) is the reduction in the responses to a common sound relative to the same sound when rare. It was originally described in the primary auditory cortex (A1) as the neuronal correlate of the mismatch negativity (MMN), an important component of the auditory event-related potentials that is elicited by changes in the auditory environment. However, the relationship between SSA and the MMN is still a subject of debate. The MMN is a mid-late potential (~ 150-200 ms in humans), and its neural sources have been located mainly within non-primary auditory cortex in humans and animal models. Moreover, SSA is also present as early as in the auditory midbrain and thalamus (IC and MGB). In this talk I will show our recent findings on recordings from single neurons in the IC, MGB and auditory cortex (AC) of anaesthetized rats to an oddball paradigm similar to that used for MMN studies. Our data demonstrate that: 1) Most neurons in the non-lemnical divisions of the IC and MGB show strong SSA; 2) the magnitude of adaptation in many IC neurons increased proportionally with frequency contrast and low probability of occurrence for deviant tones. 3) SSA varies within the neuronal receptive field. 4) GABAergic and/or glycinergic inhibition play a role in shaping SSA in the IC and MGB. 5) Acetylcholine modulates SSA by differently affecting the response to the standard sounds. And, finally, 6) our most recent recordings from different AC fields demonstrate that SSA is much stronger and develops faster in non-primary than in primary auditory cortex, paralleling the organization of subcortical SSA.Taken together our results suggest that SSA can be generated in a bottom-up manner throughout the auditory pathway and they are congruent with the notion that subcortical SSA can contribute upstream to the generation of MMN. doi:10.1016/j.ijpsycho.2016.07.067
433 Event-related potential research on prediction and attention revisited under the predictive coding umbrella Erich Schröger Leipzig University, Leipzig, Germany Event-related potential (ERP) research from various fields (e.g. Mismatch negativity, N1 suppression) revealed an interesting pattern of modulations of ERPs elicited by predictable and by unpredictable sounds: Unpredictable sounds such as sounds occurring after a long silent inter-sound interval or sounds violating an established regularity are known to elicit enhanced brain responses (e.g. the N1), while predictable sounds such as sounds occurring after several repetitions of the same sound or self-generated sounds often elicit attenuated brain responses (e.g. the N1). This pattern of results can be explained with the predictive coding theory stating that our brain processes sensory input with respect to predictions derived from a neural model representing what we (implicitly or explicitly) believe being the cause of the sensory input. It is suggested that for each arriving sound, the prediction error (PE) is computed as the difference between the top-down prediction (P) and the sensory input (I), and sent as a feedforward signal to higher