Richard Ivry | University of California, Berkeley (original) (raw)
Papers by Richard Ivry
Frontiers in Neuroscience, 2003
ABSTRACT Previous studies have suggested that the cerebellum and basal ganglia may play a critica... more ABSTRACT Previous studies have suggested that the cerebellum and basal ganglia may play a critical role in interval timing. In the first part of the chapter, we review this literature, focusing on production and perception tasks involving intervals in the hundreds of millisecond range. Overall, the neuropsychological and neuroimaging evidence consistently points to the involvement of the cerebellum in such tasks; the evidence is less consistent with respect to the basal ganglia. In the second half of the chapter, we present an experiment in which patients with either cerebellar or basal ganglia pathology were tested on a repetitive tapping task. Unlike previous studies, a pacing signal was provided, allowing an evaluation of variability associated with internal timing, motor implementation, and error correction. The results suggest a dissociation between the two groups: the patients with cerebellar lesions exhibited noisy internal timing while the gain in error correction was reduced in Parkinson patients. In combination with previous work, these results indicate how the cerebellum and basal ganglia may make differential contributions to tasks that require consistent timing. 1.
Space and Time in Perception and Action, 2010
Advances in Consciousness Research, 2003
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience
The striking homogeneity of cerebellar microanatomy is strongly suggestive of a corresponding uni... more The striking homogeneity of cerebellar microanatomy is strongly suggestive of a corresponding uniformity of function. Consequently, theoretical models of the cerebellum's role in motor control should offer important clues regarding cerebellar contributions to cognition. One such influential theory holds that the cerebellum encodes internal models, neural representations of the context-specific dynamic properties of an object, to facilitate predictive control when manipulating the object. The present study examined whether this theoretical construct can shed light on the contribution of the cerebellum to language processing. We reasoned that the cerebellum might perform a similar coordinative function when the context provided by the initial part of a sentence can be highly predictive of the end of the sentence. Using functional MRI in humans we tested two predictions derived from this hypothesis, building on previous neuroimaging studies of internal models in motor control. Firs...
Cerebral cortex (New York, N.Y. : 1991), Jan 16, 2015
In this study, we examined the dynamics of inhibitory preparatory processes, using a delayed resp... more In this study, we examined the dynamics of inhibitory preparatory processes, using a delayed response task in which a cue signaled a left or right index finger (Experiment 1) or hand (Experiment 2) movement in advance of an imperative signal. In Experiment 1, we varied the duration of the delay period (200, 500, and 900 ms). When transcranial magnetic stimulation (TMS) was applied 100 ms before the imperative, motor evoked potentials (MEPs) elicited in the first dorsal interosseous were strongly inhibited. For delays of 500 ms or longer, this inhibition was greater when the targeted muscle was selected compared with when it was not selected. In contrast, the magnitude of inhibition just after the cue was inversely related to the duration of the delay period, and the difference between the selected and nonselected conditions was attenuated. In Experiment 2, TMS and peripheral nerve stimulation procedures were used during a 300-ms delay period. MEPs in the flexor carpi radialis for bo...
Originaltext vom Verlag; nicht vom SfBS bearbeitet. Book Description: Written by leading research... more Originaltext vom Verlag; nicht vom SfBS bearbeitet. Book Description: Written by leading researchers in the field, Cognitive Neuroscience: The Biology of the Mind shows how the complex processes of the mind--language, memory, attention, feelings--are enabled by the underlying biology of the brain. Relying on patient studies and case histories rather than lab experiments on animals, the authors explore the underlying neurological chemistry behind critical human diseases, such as Alzheimer's and Parkinson's, and suggests various treatments. A series of interviews with other researchers bring the science to life as they discuss their pathbreaking discoveries and speculate about new frontiers for the discipline.
Three experiments were conducted to identify the locus of bimanual interferenceobserved during th... more Three experiments were conducted to identify the locus of bimanual interferenceobserved during the production of reaching movements. The movements had either thesame or different amplitude and were directed towards identically or differently coloredtarget circles. In Experiment 1, reaction times for movements of different amplitudes totargets of the same color were faster than for movements of the same amplitude to targetsof different colors. This indicates that the cost to initiate...
![Research paper thumbnail of A functional role for the motor system in language understanding: Evidence from rTMS [Abstract]](https://attachments.academia-assets.com/45499081/thumbnails/1.jpg)
](Does language comprehension depend, in part, on neural systems for action? In previous studies, m... more Does language comprehension depend, in part, on neural systems for action? In previous studies, motor areas of the brain were activated when people read or listened to action verbs, but it remains unclear whether such activation is functionally relevant for comprehension. In the experiments reported here, we used off-line theta-burst transcranial magnetic stimulation to investigate whether a causal relationship exists between activity in premotor cortex and action-language understanding. Right-handed participants completed a lexical decision task, in which they read verbs describing manual actions typically performed with the dominant hand (e.g., "to throw," "to write") and verbs describing nonmanual actions (e.g., "to earn," "to wander"). Responses to manual-action verbs (but not to nonmanual-action verbs) were faster after stimulation of the hand area in left premotor cortex than after stimulation of the hand area in right premotor cortex. These results suggest that premotor cortex has a functional role in action-language understanding.
APA PsycNET Our Apologies! - The following features are not available with your current Browser c... more APA PsycNET Our Apologies! - The following features are not available with your current Browser configuration. - alerts user that their session is about to expire - display, print, save, export, and email selected records - get My ...
Perception & Psychophysics
In four experiments, we examined whether the phenomenon of illusory conjunctions is constrained b... more In four experiments, we examined whether the phenomenon of illusory conjunctions is constrained by feature similarity. Specifically, are illusory conjunctions more likely to occur between items with similar features than between items with dissimilar features? Feature similarity was manipulated in two dimensions: color and shape. Experiment 1 demonstrated that more illusory conjunctions occur between items with similar colors than between items with dissimilar colors. A similar effect was found for letter similarity in Experiment 2. Experiments 3 and 4 demonstrated that the similarity effect is still obtained for illusory conjunctions even when identification of the relevant features is near perfect. These findings introduce a new constraint in the process of feature integration. Additional implications of the similarity constraint for theories of feature integration are discussed.
Perception & Psychophysics
The effects of sensory signal characteristics on the duration discrimination of intermodal interv... more The effects of sensory signal characteristics on the duration discrimination of intermodal intervals was investigated in three experiments. Temporal intervals were marked by either the successive presentation of a visual then auditory signal (VA), or by the successive presentation of an auditory then visual signal (AV). The results indicated that (1) VA intervals are generally easier to discriminate than are AV intervals, but this effect depends on the range of duration studied; (2) AV intervals are perceived as longer than VA intervals for durations ranging from 250 to 750 msec; (3) the intensity of the visual markers for both AV and VA intervals does not affect the discrimination; and (4) the perceived duration of an intermodal interval is influenced by the length of the first and second markers. The results are mainly interpreted in terms of (1) a sensory trace left by visual and auditory signals and (2) the detection of these signals.
Journal of Applied Geophysics
International Review of Psychiatry
We review evidence from neuropsychological studies of patients with damage to the cerebellum that... more We review evidence from neuropsychological studies of patients with damage to the cerebellum that suggests cerebellar involvement in four general categories of cognition: (1) speech and language; (2) temporal processing; (3) implicit learning and memory; (4) visuospatial processing and attention. A relatively strong case can be made for cerebellar contributions to language (including speech perception, lexical retrieval, and working memory) and to temporal processing. However, the evidence concerning cerebellar involvement in non-motor implicit learning and visuospatial processing is more equivocal. We argue that cerebellar contributions to cognition are computationally plausible, given its reciprocal connectivity with the cerebral cortex, and suggest that this function of the cerebellum may be an example of an evolutionary process by which mechanisms originally evolved for one function (in this case, motor control) are adapted to other functions (cognition).
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience
Positron emission tomography was used to identify neural systems involved in the acquisition and ... more Positron emission tomography was used to identify neural systems involved in the acquisition and expression of sequential movements produced by different effectors. Subjects were tested on the serial reaction time task under implicit learning conditions. In the initial acquisition phase, subjects responded to the stimuli with keypresses using the four fingers of the right hand. During this phase, the stimuli followed a fixed sequence for one group of subjects (group A) and were randomly selected for another group (group B). In the transfer phase, arm movements were used to press keys on a substantially larger keyboard, and for both groups, the stimuli followed the sequence. Behavioral indices provided clear evidence of learning during the acquisition phase for group A and transfer when switched to the large keyboard. Sequence acquisition was associated with learning-related increases in regional cerebral blood flow (rCBF) in a network of areas in the contralateral left hemisphere, i...
this article, we review evidence obtained by such experiments related to four general categories ... more this article, we review evidence obtained by such experiments related to four general categories of function: those involving language, temporal processing, implicit learning and memory, and visuospatial processing and attention. Given the links between the cerebellum and motor control, it is not surprising that many of the hypothesised cognitive roles are, at least metaphorically, related to movement
In the unloading task, a weight is held in the palm of one hand. When an external agent removes t... more In the unloading task, a weight is held in the palm of one hand. When an external agent removes the weight, an upward perturbation of the loaded hand is observed. However, when a person removes the weight by lifting it with their own hand, the perturbation is attenuated due to an anticipatory adjustment of the flexor muscles in the load-bearing arm. An experiment was conducted to examine conditions under which this anticipatory response could be learned. Using a virtual reality system with force-feedback robotic arms, normal subjects performed the unloading task under one of four learning conditions: (a) the participant initiated the unloading by pressing a button, (b) the unloading was cued by a brief visual stimulus, (c) the unloading was performed by a virtual "hand" that moved smoothly towards the object, and (d) the unloading followed three rhythmic force-pulses applied to the finger of the participant. After extended practice (192 trials) we found a significant reduc...
Frontiers in Neuroscience, 2003
ABSTRACT Previous studies have suggested that the cerebellum and basal ganglia may play a critica... more ABSTRACT Previous studies have suggested that the cerebellum and basal ganglia may play a critical role in interval timing. In the first part of the chapter, we review this literature, focusing on production and perception tasks involving intervals in the hundreds of millisecond range. Overall, the neuropsychological and neuroimaging evidence consistently points to the involvement of the cerebellum in such tasks; the evidence is less consistent with respect to the basal ganglia. In the second half of the chapter, we present an experiment in which patients with either cerebellar or basal ganglia pathology were tested on a repetitive tapping task. Unlike previous studies, a pacing signal was provided, allowing an evaluation of variability associated with internal timing, motor implementation, and error correction. The results suggest a dissociation between the two groups: the patients with cerebellar lesions exhibited noisy internal timing while the gain in error correction was reduced in Parkinson patients. In combination with previous work, these results indicate how the cerebellum and basal ganglia may make differential contributions to tasks that require consistent timing. 1.
Space and Time in Perception and Action, 2010
Advances in Consciousness Research, 2003
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience
The striking homogeneity of cerebellar microanatomy is strongly suggestive of a corresponding uni... more The striking homogeneity of cerebellar microanatomy is strongly suggestive of a corresponding uniformity of function. Consequently, theoretical models of the cerebellum's role in motor control should offer important clues regarding cerebellar contributions to cognition. One such influential theory holds that the cerebellum encodes internal models, neural representations of the context-specific dynamic properties of an object, to facilitate predictive control when manipulating the object. The present study examined whether this theoretical construct can shed light on the contribution of the cerebellum to language processing. We reasoned that the cerebellum might perform a similar coordinative function when the context provided by the initial part of a sentence can be highly predictive of the end of the sentence. Using functional MRI in humans we tested two predictions derived from this hypothesis, building on previous neuroimaging studies of internal models in motor control. Firs...
Cerebral cortex (New York, N.Y. : 1991), Jan 16, 2015
In this study, we examined the dynamics of inhibitory preparatory processes, using a delayed resp... more In this study, we examined the dynamics of inhibitory preparatory processes, using a delayed response task in which a cue signaled a left or right index finger (Experiment 1) or hand (Experiment 2) movement in advance of an imperative signal. In Experiment 1, we varied the duration of the delay period (200, 500, and 900 ms). When transcranial magnetic stimulation (TMS) was applied 100 ms before the imperative, motor evoked potentials (MEPs) elicited in the first dorsal interosseous were strongly inhibited. For delays of 500 ms or longer, this inhibition was greater when the targeted muscle was selected compared with when it was not selected. In contrast, the magnitude of inhibition just after the cue was inversely related to the duration of the delay period, and the difference between the selected and nonselected conditions was attenuated. In Experiment 2, TMS and peripheral nerve stimulation procedures were used during a 300-ms delay period. MEPs in the flexor carpi radialis for bo...
Originaltext vom Verlag; nicht vom SfBS bearbeitet. Book Description: Written by leading research... more Originaltext vom Verlag; nicht vom SfBS bearbeitet. Book Description: Written by leading researchers in the field, Cognitive Neuroscience: The Biology of the Mind shows how the complex processes of the mind--language, memory, attention, feelings--are enabled by the underlying biology of the brain. Relying on patient studies and case histories rather than lab experiments on animals, the authors explore the underlying neurological chemistry behind critical human diseases, such as Alzheimer's and Parkinson's, and suggests various treatments. A series of interviews with other researchers bring the science to life as they discuss their pathbreaking discoveries and speculate about new frontiers for the discipline.
Three experiments were conducted to identify the locus of bimanual interferenceobserved during th... more Three experiments were conducted to identify the locus of bimanual interferenceobserved during the production of reaching movements. The movements had either thesame or different amplitude and were directed towards identically or differently coloredtarget circles. In Experiment 1, reaction times for movements of different amplitudes totargets of the same color were faster than for movements of the same amplitude to targetsof different colors. This indicates that the cost to initiate...
Does language comprehension depend, in part, on neural systems for action? In previous studies, m... more Does language comprehension depend, in part, on neural systems for action? In previous studies, motor areas of the brain were activated when people read or listened to action verbs, but it remains unclear whether such activation is functionally relevant for comprehension. In the experiments reported here, we used off-line theta-burst transcranial magnetic stimulation to investigate whether a causal relationship exists between activity in premotor cortex and action-language understanding. Right-handed participants completed a lexical decision task, in which they read verbs describing manual actions typically performed with the dominant hand (e.g., "to throw," "to write") and verbs describing nonmanual actions (e.g., "to earn," "to wander"). Responses to manual-action verbs (but not to nonmanual-action verbs) were faster after stimulation of the hand area in left premotor cortex than after stimulation of the hand area in right premotor cortex. These results suggest that premotor cortex has a functional role in action-language understanding.
APA PsycNET Our Apologies! - The following features are not available with your current Browser c... more APA PsycNET Our Apologies! - The following features are not available with your current Browser configuration. - alerts user that their session is about to expire - display, print, save, export, and email selected records - get My ...
Perception & Psychophysics
In four experiments, we examined whether the phenomenon of illusory conjunctions is constrained b... more In four experiments, we examined whether the phenomenon of illusory conjunctions is constrained by feature similarity. Specifically, are illusory conjunctions more likely to occur between items with similar features than between items with dissimilar features? Feature similarity was manipulated in two dimensions: color and shape. Experiment 1 demonstrated that more illusory conjunctions occur between items with similar colors than between items with dissimilar colors. A similar effect was found for letter similarity in Experiment 2. Experiments 3 and 4 demonstrated that the similarity effect is still obtained for illusory conjunctions even when identification of the relevant features is near perfect. These findings introduce a new constraint in the process of feature integration. Additional implications of the similarity constraint for theories of feature integration are discussed.
Perception & Psychophysics
The effects of sensory signal characteristics on the duration discrimination of intermodal interv... more The effects of sensory signal characteristics on the duration discrimination of intermodal intervals was investigated in three experiments. Temporal intervals were marked by either the successive presentation of a visual then auditory signal (VA), or by the successive presentation of an auditory then visual signal (AV). The results indicated that (1) VA intervals are generally easier to discriminate than are AV intervals, but this effect depends on the range of duration studied; (2) AV intervals are perceived as longer than VA intervals for durations ranging from 250 to 750 msec; (3) the intensity of the visual markers for both AV and VA intervals does not affect the discrimination; and (4) the perceived duration of an intermodal interval is influenced by the length of the first and second markers. The results are mainly interpreted in terms of (1) a sensory trace left by visual and auditory signals and (2) the detection of these signals.
Journal of Applied Geophysics
International Review of Psychiatry
We review evidence from neuropsychological studies of patients with damage to the cerebellum that... more We review evidence from neuropsychological studies of patients with damage to the cerebellum that suggests cerebellar involvement in four general categories of cognition: (1) speech and language; (2) temporal processing; (3) implicit learning and memory; (4) visuospatial processing and attention. A relatively strong case can be made for cerebellar contributions to language (including speech perception, lexical retrieval, and working memory) and to temporal processing. However, the evidence concerning cerebellar involvement in non-motor implicit learning and visuospatial processing is more equivocal. We argue that cerebellar contributions to cognition are computationally plausible, given its reciprocal connectivity with the cerebral cortex, and suggest that this function of the cerebellum may be an example of an evolutionary process by which mechanisms originally evolved for one function (in this case, motor control) are adapted to other functions (cognition).
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience
Positron emission tomography was used to identify neural systems involved in the acquisition and ... more Positron emission tomography was used to identify neural systems involved in the acquisition and expression of sequential movements produced by different effectors. Subjects were tested on the serial reaction time task under implicit learning conditions. In the initial acquisition phase, subjects responded to the stimuli with keypresses using the four fingers of the right hand. During this phase, the stimuli followed a fixed sequence for one group of subjects (group A) and were randomly selected for another group (group B). In the transfer phase, arm movements were used to press keys on a substantially larger keyboard, and for both groups, the stimuli followed the sequence. Behavioral indices provided clear evidence of learning during the acquisition phase for group A and transfer when switched to the large keyboard. Sequence acquisition was associated with learning-related increases in regional cerebral blood flow (rCBF) in a network of areas in the contralateral left hemisphere, i...
this article, we review evidence obtained by such experiments related to four general categories ... more this article, we review evidence obtained by such experiments related to four general categories of function: those involving language, temporal processing, implicit learning and memory, and visuospatial processing and attention. Given the links between the cerebellum and motor control, it is not surprising that many of the hypothesised cognitive roles are, at least metaphorically, related to movement
In the unloading task, a weight is held in the palm of one hand. When an external agent removes t... more In the unloading task, a weight is held in the palm of one hand. When an external agent removes the weight, an upward perturbation of the loaded hand is observed. However, when a person removes the weight by lifting it with their own hand, the perturbation is attenuated due to an anticipatory adjustment of the flexor muscles in the load-bearing arm. An experiment was conducted to examine conditions under which this anticipatory response could be learned. Using a virtual reality system with force-feedback robotic arms, normal subjects performed the unloading task under one of four learning conditions: (a) the participant initiated the unloading by pressing a button, (b) the unloading was cued by a brief visual stimulus, (c) the unloading was performed by a virtual "hand" that moved smoothly towards the object, and (d) the unloading followed three rhythmic force-pulses applied to the finger of the participant. After extended practice (192 trials) we found a significant reduc...