Monday, April 30, 2012
Friday, April 27, 2012
SFN Abstract Submission now open
the final day to submit is may 10th
http://www.sfn.org/am2012/index.aspx?pagename=call_for_abstracts
http://www.sfn.org/am2012/index.aspx?pagename=call_for_abstracts
CNS Seminar: Jon Wallis
April 1st
Jon Wallis
Dept of Psychology
UC Berkeley
Prefrontal computations underlying decision-making
Abstract. Damage to frontal cortex can produce a very specific deficit in decision-making. Patients make terrible life decisions and yet in all other respects their cognitive abilities are intact. My research aims to understand what computations frontal neurons perform that enable normal decision-making. We train monkeys to perform simple decision-making tasks while we record the activity of many single
neurons throughout the frontal cortex. In this talk, I will describe a series of experiments in which we have dissociated the computations performed by two subregions of the frontal cortex: the orbitofrontal cortex (OFC) and the anterior cingulate cortex (ACC).
Our results are compatible with a two-stage model of decision-making. In this model, OFC is responsible for first calculating the motivational value of sensory stimuli in the environment. This is accomplished by integrating multiple decision parameters into a single abstract measure of value. This information is then passed to ACC where it can be used to determine the value of potential actions. ACC neurons do this by incorporating information about action costs into the value signal. In addition, ACC is responsible for monitoring whether the expected outcome of the action matches the actual outcome. In this way, OFC and ACC jointly ensure that our actions are optimal with respect to realizing our motivational needs.
Jon Wallis
Dept of Psychology
UC Berkeley
Prefrontal computations underlying decision-making
Abstract. Damage to frontal cortex can produce a very specific deficit in decision-making. Patients make terrible life decisions and yet in all other respects their cognitive abilities are intact. My research aims to understand what computations frontal neurons perform that enable normal decision-making. We train monkeys to perform simple decision-making tasks while we record the activity of many single
neurons throughout the frontal cortex. In this talk, I will describe a series of experiments in which we have dissociated the computations performed by two subregions of the frontal cortex: the orbitofrontal cortex (OFC) and the anterior cingulate cortex (ACC).
Our results are compatible with a two-stage model of decision-making. In this model, OFC is responsible for first calculating the motivational value of sensory stimuli in the environment. This is accomplished by integrating multiple decision parameters into a single abstract measure of value. This information is then passed to ACC where it can be used to determine the value of potential actions. ACC neurons do this by incorporating information about action costs into the value signal. In addition, ACC is responsible for monitoring whether the expected outcome of the action matches the actual outcome. In this way, OFC and ACC jointly ensure that our actions are optimal with respect to realizing our motivational needs.
Monday, April 23, 2012
CNS Seminar: Ayse Saygin
April 24th
Ayse Saygin
Dept of Cognitive Science
UC San Diego
Perceptual and Neural Processing of Body Movements Studied with Dots and ‘Bots
Abstract. The perception of others’ body movements and actions is important for hunting prey, avoiding predators, communication, social interaction... In primates, the perception of body movements is supported by network of temporal, parietal and frontal brain areas. Our goal is to elucidate functional properties of this system using behavioral, neuroimaging and neuropsychological studies. I will present work with two kinds of stimuli that allow us to focus on the role of visual form and visual motion in body movement perception. Neuroimaging, neuropsychological and transcranial magnetic stimulation experiments with “dots” (point-light biological motion), allow us to focus on the role of motion in body movement processing (though it turns out it is difficult to abstract away from form even with these stimuli). To manipulate visual form and visual motion in fully illuminated stimuli of body movements, we also use a stimulus set of actions carried out by humans as well as "bots" (humanoid robots) in fMRI and EEG studies. Together, these studies highlight the importance and necessity of a network of brain regions for body movement perception, but suggest the functional properties of this system and the underlying neural computations need to be further specified.
Ayse Saygin
Dept of Cognitive Science
UC San Diego
Perceptual and Neural Processing of Body Movements Studied with Dots and ‘Bots
Abstract. The perception of others’ body movements and actions is important for hunting prey, avoiding predators, communication, social interaction... In primates, the perception of body movements is supported by network of temporal, parietal and frontal brain areas. Our goal is to elucidate functional properties of this system using behavioral, neuroimaging and neuropsychological studies. I will present work with two kinds of stimuli that allow us to focus on the role of visual form and visual motion in body movement perception. Neuroimaging, neuropsychological and transcranial magnetic stimulation experiments with “dots” (point-light biological motion), allow us to focus on the role of motion in body movement processing (though it turns out it is difficult to abstract away from form even with these stimuli). To manipulate visual form and visual motion in fully illuminated stimuli of body movements, we also use a stimulus set of actions carried out by humans as well as "bots" (humanoid robots) in fMRI and EEG studies. Together, these studies highlight the importance and necessity of a network of brain regions for body movement perception, but suggest the functional properties of this system and the underlying neural computations need to be further specified.
Friday, April 13, 2012
2 great talks next week
Our CNS seminar on tuesday and then the Psych Colloquium on Thursday
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Cognitive Neural Systems Seminar Series
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Tuesday, April 17th, 12pm
Marlene Behrmann
Dept of Psychology
Carnegie Mellon University
Distributed neural circuits, not circumscribed centers, mediate both face and word recognition
Abstract. In contrast with the claim that there are domain-specific neural correlates underlying face and word recognition, I will propose that complex visual recognition is subserved by a distributed underlying circuit that becomes tuned, over the course of development, to be optimized, in the left hemisphere, for orthographic inputs, and, in the right hemisphere, for faces. Corresponding behavioral and neural evidence obtained from normal children, adolescents and adults, revealing the developmental trajectory of this behavior/brain system, as well as from individuals with prosopagnosia (congenital and acquired) will be presented with specific emphasis on the relative contribution of the nodes of this network as revealed by functional and structural connectivity as well as resting state studies.
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Department of Psychology Colloquium
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Thursday, April 19th, 4pm
Ione Fine
Dept of Psychology
University of Washington
The recruitment of visual motion area MT for auditory motion processing in early blind individuals
Abstract. Examining people who are blind from birth provides a powerful way to examine how sensory input determines cortical organization because normally almost 30% of cerebral cortex is devoted to vision. Here I will describe a series of studies examining motion-sensitive area MT+ in individuals who have been blind from early childhood, and in two rare sight-recovery subjects who were blind since early childhood and whose vision was partially recovered in adulthood. While most visual form processing is severely impaired by blindness, visual motion processing remains surprisingly robust after years of deprivation. Curiously, these robust visual motion responses co-exist with strong cross-modal plasticity. In early blind and sight recovery subjects we see responses to within MT+ that are specific to auditory motion compared with other complex auditory stimuli. Thus, MT+ develops motion-specific responses to nonvisual input that seems to be influenced by the normal functional specialization of that area. Further, these responses within MT+ are associated with behavioral choice on a trial-by-trial basis, are associated with superior auditory motion performance within blind individuals, and replace rather than augment the region of auditory cortex (planum temporale) associated with the processing of auditory motion within sighted individuals.
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Cognitive Neural Systems Seminar Series
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Tuesday, April 17th, 12pm
Marlene Behrmann
Dept of Psychology
Carnegie Mellon University
Distributed neural circuits, not circumscribed centers, mediate both face and word recognition
Abstract. In contrast with the claim that there are domain-specific neural correlates underlying face and word recognition, I will propose that complex visual recognition is subserved by a distributed underlying circuit that becomes tuned, over the course of development, to be optimized, in the left hemisphere, for orthographic inputs, and, in the right hemisphere, for faces. Corresponding behavioral and neural evidence obtained from normal children, adolescents and adults, revealing the developmental trajectory of this behavior/brain system, as well as from individuals with prosopagnosia (congenital and acquired) will be presented with specific emphasis on the relative contribution of the nodes of this network as revealed by functional and structural connectivity as well as resting state studies.
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Department of Psychology Colloquium
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Thursday, April 19th, 4pm
Ione Fine
Dept of Psychology
University of Washington
The recruitment of visual motion area MT for auditory motion processing in early blind individuals
Abstract. Examining people who are blind from birth provides a powerful way to examine how sensory input determines cortical organization because normally almost 30% of cerebral cortex is devoted to vision. Here I will describe a series of studies examining motion-sensitive area MT+ in individuals who have been blind from early childhood, and in two rare sight-recovery subjects who were blind since early childhood and whose vision was partially recovered in adulthood. While most visual form processing is severely impaired by blindness, visual motion processing remains surprisingly robust after years of deprivation. Curiously, these robust visual motion responses co-exist with strong cross-modal plasticity. In early blind and sight recovery subjects we see responses to within MT+ that are specific to auditory motion compared with other complex auditory stimuli. Thus, MT+ develops motion-specific responses to nonvisual input that seems to be influenced by the normal functional specialization of that area. Further, these responses within MT+ are associated with behavioral choice on a trial-by-trial basis, are associated with superior auditory motion performance within blind individuals, and replace rather than augment the region of auditory cortex (planum temporale) associated with the processing of auditory motion within sighted individuals.
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Friday, April 6, 2012
CNS Seminar: Sonia Bishop
Tuesday, April 10th
Sonia Bishop
Department of Psychology
UC Berkeley
An individual differences perspective on anxiety and worry: frontal engagement in attentional control and mind wandering.
Abstract. Worry, distractibility, and difficulty concentrating are symptomatic of both clinical and subclinical anxiety. Many empirical studies have reported that anxious individuals show threat-related biases in selective attention. Early cognitive models of anxiety argued that these biases result from amplification of the signal from a pre-attentive threat detection mechanism, this boosting the ability of threat distractors to compete for attention. There is evidence, however, that anxiety may also be linked to impoverished attentional control. Specifically, neuroimaging studies of selective attention indicate that anxious individuals show impoverished recruitment of the frontal brain regions implicated in attentional control and that this is observed regardless of whether attentional competition is created by threat-related stimuli or response conflict. While the role of disrupted frontal control of attention in anxiety is becoming increasingly recognized, there has been little investigation of how this relates to worry. In general, there has been little attempt to differentiate the constructs of trait anxiety and worry using neurocognitive approaches. Here, I will present data from a recent study investigating how individual differences in trait anxiety and worry influence performance, and associated engagement of frontal cortical regions, during a task of sustained attention. The need to disentangle DLPFC involvement in attentional control versus task-unrelated thought, and the implications of our findings for current models of mind-wandering will be discussed.
Sonia Bishop
Department of Psychology
UC Berkeley
An individual differences perspective on anxiety and worry: frontal engagement in attentional control and mind wandering.
Abstract. Worry, distractibility, and difficulty concentrating are symptomatic of both clinical and subclinical anxiety. Many empirical studies have reported that anxious individuals show threat-related biases in selective attention. Early cognitive models of anxiety argued that these biases result from amplification of the signal from a pre-attentive threat detection mechanism, this boosting the ability of threat distractors to compete for attention. There is evidence, however, that anxiety may also be linked to impoverished attentional control. Specifically, neuroimaging studies of selective attention indicate that anxious individuals show impoverished recruitment of the frontal brain regions implicated in attentional control and that this is observed regardless of whether attentional competition is created by threat-related stimuli or response conflict. While the role of disrupted frontal control of attention in anxiety is becoming increasingly recognized, there has been little investigation of how this relates to worry. In general, there has been little attempt to differentiate the constructs of trait anxiety and worry using neurocognitive approaches. Here, I will present data from a recent study investigating how individual differences in trait anxiety and worry influence performance, and associated engagement of frontal cortical regions, during a task of sustained attention. The need to disentangle DLPFC involvement in attentional control versus task-unrelated thought, and the implications of our findings for current models of mind-wandering will be discussed.
Wednesday, April 4, 2012
Richard Dawkins talk in San Diego, April 6
it looks like this event will be about his more recent science/religion writings.
more information here
more information here
Monday, April 2, 2012
CNS Seminar: Andrei Kozlov
April 3rd
Andrei Kozlov
Dept of Psychology
UC San Diego
Sensitivity, selectivity and invariance in the auditory system
Abstract. In this talk, I will describe two problems faced by the auditory system at two different levels of organization. The first problem arises in the cochlea during the conversion of a sound into an electrical signal. Although von Helmholtz recognized in the 19th Century that the ear contains an array of resonators like a piano that contains an array of strings tuned to particular frequencies, viscous friction in the liquid that fills the inner ear prohibits any passive resonance. Like the strings of a piano in honey, the ear’s mechanotransduction elements are over-damped and will not resonate unless several conditions are satisfied. I will demonstrate that the balance of the viscous, inertial, and elastic forces in the ear’s mechanotransduction organelle, the hair bundle, minimizes viscous friction and thus makes the sensitive hearing possible. The solution to this problem reflects general principles of fluid-structure interaction that apply to other biological and non-biological systems at small Reynolds numbers.
The second problem relates to how the auditory system forms selective and invariant representations of natural communication signals. Classical models[2] of pattern recognition, developed in the visual system, achieve selectivity and invariance by assigning to individual cortical neurons either a computation equivalent to logical “AND”, or one equivalent to logical “OR”. I will demonstrate in the auditory system of a songbird using natural stimuli that individual neurons perform both operations. Unlike the fixed mapping between neurons and computations in the models of visual object recognition, auditory neurons’ input-output logic is flexible, stimulus-dependent and influenced by sensory adaptation.
Andrei Kozlov
Dept of Psychology
UC San Diego
Sensitivity, selectivity and invariance in the auditory system
Abstract. In this talk, I will describe two problems faced by the auditory system at two different levels of organization. The first problem arises in the cochlea during the conversion of a sound into an electrical signal. Although von Helmholtz recognized in the 19th Century that the ear contains an array of resonators like a piano that contains an array of strings tuned to particular frequencies, viscous friction in the liquid that fills the inner ear prohibits any passive resonance. Like the strings of a piano in honey, the ear’s mechanotransduction elements are over-damped and will not resonate unless several conditions are satisfied. I will demonstrate that the balance of the viscous, inertial, and elastic forces in the ear’s mechanotransduction organelle, the hair bundle, minimizes viscous friction and thus makes the sensitive hearing possible. The solution to this problem reflects general principles of fluid-structure interaction that apply to other biological and non-biological systems at small Reynolds numbers.
The second problem relates to how the auditory system forms selective and invariant representations of natural communication signals. Classical models[2] of pattern recognition, developed in the visual system, achieve selectivity and invariance by assigning to individual cortical neurons either a computation equivalent to logical “AND”, or one equivalent to logical “OR”. I will demonstrate in the auditory system of a songbird using natural stimuli that individual neurons perform both operations. Unlike the fixed mapping between neurons and computations in the models of visual object recognition, auditory neurons’ input-output logic is flexible, stimulus-dependent and influenced by sensory adaptation.
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