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54
Predictive reward signal of dopamine neurons
- Journal of Neurophysiology
, 1998
"... Schultz, Wolfram. Predictive reward signal of dopamine neurons. is called rewards, which elicit and reinforce approach behav-J. Neurophysiol. 80: 1–27, 1998. The effects of lesions, receptor ior. The functions of rewards were developed further during blocking, electrical self-stimulation, and drugs ..."
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Cited by 747 (12 self)
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Schultz, Wolfram. Predictive reward signal of dopamine neurons. is called rewards, which elicit and reinforce approach behav-J. Neurophysiol. 80: 1–27, 1998. The effects of lesions, receptor ior. The functions of rewards were developed further during blocking, electrical self-stimulation, and drugs of abuse suggest the evolution of higher mammals to support more sophistithat midbrain dopamine systems are involved in processing reward cated forms of individual and social behavior. Thus biologiinformation and learning approach behavior. Most dopamine neucal and cognitive needs define the nature of rewards, and rons show phasic activations after primary liquid and food rewards and conditioned, reward-predicting visual and auditory stimuli. the availability of rewards determines some of the basic They show biphasic, activation-depression responses after stimuli parameters of the subject’s life conditions. that resemble reward-predicting stimuli or are novel or particularly Rewards come in various physical forms, are highly variable salient. However, only few phasic activations follow aversive stim-in time and depend on the particular environment of the subject. uli. Thus dopamine neurons label environmental stimuli with appe- Despite their importance, rewards do not influence the brain titive value, predict and detect rewards and signal alerting and motivating events. By failing to discriminate between different
A Computational Theory of Executive Cognitive Processes and Multiple-Task Performance: Part 2. . .
- PSYCHOLOGICAL REVIEW
, 1997
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A model of corticostriatal plasticity for learning oculomotor associations and sequences
- Journal of Cognitive Neuroscience
, 1995
"... H We present models that learn contextdependent oculomotor behavior in (1) conditional visual discrimination and (2) sequence reproduction tasks, based on the following three principles: (1) Visual input and efferent copies of motor output produce patterns of activity in cortex. (2) Cortex influence ..."
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Cited by 68 (23 self)
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H We present models that learn contextdependent oculomotor behavior in (1) conditional visual discrimination and (2) sequence reproduction tasks, based on the following three principles: (1) Visual input and efferent copies of motor output produce patterns of activity in cortex. (2) Cortex influences the saccade system in part via corticostriatal projections. (3) A reinforcement learning mechanism modifies corticostriatal synapses to link patterns of cortical activity to the correct saccade responses during trial-and-error learning. Our conditional visual discrimination model learns to associate visual cues with the corresponding saccades to one of two left-right targets. A visual cue produces patterns of neuronal activity in inferotemporal cortex (IT) that projects to the ocuIomotor region of the striatum. Initially random saccadic “guesses, ” when directed to
Event-based prospective memory and executive control of working memory
- Journal of Experimental Psychology: Learning, Memory, and Cognition
, 1998
"... In 5 experiments, the character of concurrent cognitive processing was manipulated during an event-based prospective memory task. High- and low-load conditions that differed only in the difficulty of the concurrent task were tested in each experiment. In Experiments 1 and 2, attention-demanding task ..."
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Cited by 64 (15 self)
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In 5 experiments, the character of concurrent cognitive processing was manipulated during an event-based prospective memory task. High- and low-load conditions that differed only in the difficulty of the concurrent task were tested in each experiment. In Experiments 1 and 2, attention-demanding tasks from the literature on executive control produced decrements in prospective memory. In Experiment 3, attention was divided by different loads of articulatory suppression that did not ultimately lead to decrements in prospective memory. A high-load manipulation of a visuospatial task requiring performance monitoring resulted in worse prospective memory in Experiment 4, whereas in Experiment 5 a visuospatial task with little monitoring did not. Results are discussed in terms of executive functions, such as planning and monitoring, that appear to be critical to successful event-based prospective memory. Successfully completing an intended action in the future depends on a type of remembering that has been labeled prospective memory. Thus, successful prospective memory requires remembering to remember. As a cognitive con-struct, however, prospective memory is less monolithic than
Active versus latent representations: A neural network model of perseveration and dissociation in early childhood
- Developmental Psychobiology
, 2002
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Semantic retrieval, mnemonic control, and prefrontal cortex. Behav Cogn Neurosci Rev 1
, 2002
"... The online version of this article can be found at: ..."
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Cited by 51 (5 self)
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The online version of this article can be found at:
Animal Foraging and the Evolution of Goal-Directed Cognition
- Cognitive Science
, 2006
"... Foraging- and feeding-related behaviors across eumetazoans share similar molecular mechanisms, suggesting the early evolution of an optimal foraging behavior called area-restricted search (ARS), involving mechanisms of dopamine and glutamate in the modulation of behavioral focus. Similar mechanisms ..."
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Cited by 32 (11 self)
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Foraging- and feeding-related behaviors across eumetazoans share similar molecular mechanisms, suggesting the early evolution of an optimal foraging behavior called area-restricted search (ARS), involving mechanisms of dopamine and glutamate in the modulation of behavioral focus. Similar mechanisms in the vertebrate basal ganglia control motor behavior and cognition and reveal an evolutionary progression toward increasing internal connections between prefrontal cortex and striatum in moving from amphibian to primate. The basal ganglia in higher vertebrates show the ability to transfer dopaminergic activity from unconditioned stimuli to conditioned stimuli. The evolutionary role of dopamine in the modulation of goal-directed behavior and cognition is further supported by pathologies of human goal-directed cognition, which have motor and cognitive dysfunction and organize themselves, with respect to dopaminergic activity, along the gradient described by ARS, from perseverative to unfocused. The evidence strongly supports the evolution of goal-directed cognition out of mechanisms initially in control of spatial foraging but, through increasing cortical connections, eventually used to forage for information.
A systems-level perspective on attention and cognitive control: Guided activation, adaptive gating, conflict monitoring, and exploitation vs. exploration, chapter 6
- In M. I. Posner (Ed.), Cognitive
, 2004
"... An understanding of attention is arguably one of the most important goals of the cognitive sciences and yet also has proven to be one of the most elusive. Most attention researchers will agree that a major problem has been agreeing on a definition of the term and the scope of the phenomena to which ..."
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Cited by 26 (1 self)
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An understanding of attention is arguably one of the most important goals of the cognitive sciences and yet also has proven to be one of the most elusive. Most attention researchers will agree that a major problem has been agreeing on a definition of the term and the scope of the phenomena to which it applies. There are no doubt as many explanations for this state of affairs as there are those who consider themselves “attention researchers. ” However, most will probably agree that, in large measure, this is because attention is not a unitary phenomenon—at least not in the sense that it reflects the operation of a single mechanism, or a single function of one or a set of mechanisms. Rather, attention is the emergent property of the cognitive system that allows it to successfully process some sources of information to the exclusion of others, in the service of achieving some goals to the exclusion of others. This begs an important question: If attention is so varied a phenomenon, how can we make progress in understanding it? There are two simple answers to this question: Be precise about the specific (aspects of the) phenomena to be studied, and be precise about the mechanisms thought to explain them. In this chapter, we address a particular type of attentional phenomenon—that associated
Emotion and Learning: A computational model of the amygdala
, 2002
"... We describe work in progress with the aim of constructing a computational model of emotional learning and processing inspired by neurophysiological ¢ndings. The main brain areas modeled are the amygdala and the orbitofrontal cortex and the interaction between them. We want to show that (1) there exi ..."
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Cited by 23 (2 self)
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We describe work in progress with the aim of constructing a computational model of emotional learning and processing inspired by neurophysiological ¢ndings. The main brain areas modeled are the amygdala and the orbitofrontal cortex and the interaction between them. We want to show that (1) there exists enough physiological data to suggest the overall architecture of a computational model, (2) emotion plays a clear role in learning the behavior. We review neurophysiological data and present a computational model that is subsequently tested in simulation. In Mowrer’s in£uential two-process theory of learning, the acquisition of a learned response was considered to proceed in two steps (Mowrer, 1960/1973). In the ¢rst step, the stimulus is associated with its emotional consequences. In the second step, this emotional evaluation shapes an association between the stimulus and the response. Mowrer made an important contribution to learning theory when he acknowledged that emotion plays an important role in learning. Another important aspect of the theory is that it suggests a role for emotions that can easily be implemented as a computational model. Different versions of the two-process theory have been implemented as computational models,
Neural Mechanisms for Access to Consciousness
- In M. Gazzaniga (Ed.), the Cognitive Neurosciences III
, 2003
"... Introduction: the challenge of a science of consciousness Understanding consciousness has become the ultimate intellectual challenge of this new millennium. Even if philosophers now accept the notion that it is a "real , natural, biological phenomenon literally located in the brain" (Revo ..."
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Cited by 23 (1 self)
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Introduction: the challenge of a science of consciousness Understanding consciousness has become the ultimate intellectual challenge of this new millennium. Even if philosophers now accept the notion that it is a "real , natural, biological phenomenon literally located in the brain" (Revonsuo, 2001), a view in harmony with the neuroscientist conception that "consciousness is entirely caused by neurobiological processes and realized in brain structures" (Changeux, 1983; Crick, 1994; Edelman, 1989), the real issue becomes: how to elaborate a science of consciousness? This challenging problem raises two questions. A first one is how to empirically define experimental paradigms in order to delineate a relevant and ultimately causal relationship between subjective phenomena and objective measurements of neural activity. Cognitive psychologists have now defined a variety of minimal experimental protocols which allow a fair comparison between conscious and non-conscious processing of informa
