1,720,974 research outputs found
The NMDAr antagonist ketamine interferes with manipulation of information for transitive inference reasoning in non-human primates.
No full textOne of the most remarkable traits of highly encephalized animals is their ability to manipulate knowledge flexibly to infer logical relationships. Operationally, the corresponding cognitive process can be defined as reasoning. One hypothesis is that this process relies on the reverberating activity of glutamate neural circuits, sustained by NMDA receptor (NMDAr) mediated synaptic transmission, in both parietal and prefrontal areas. We trained two macaque monkeys to perform a form of deductive reasoning - the transitive inference task - in which they were required to learn the relationship between six adjacent items in a single session and then deduct the relationship between nonadjacent items that had not been paired in the learning phase. When the animals had learned the sequence, we administered systemically a subanaesthetic dose of ketamine (a NMDAr antagonist) and measured their performance on learned and novel problems. We observed impairments in determining the relationship between novel pairs of items. Our results are consistent with the hypothesis that transitive inference premises are integrated during learning in a unified representation and that reducing NMDAr activity interferes with the use of this mental model, when decisions are required in comparing pairs of items that have not been learned. © The Author(s) 2014
Probing the response of dorsal premotor cortex neurons during a transitive inference task in macaque monkeys
No full textNeural correlates of relational reasoning: prefrontal cortex neurons encode the value of the premises for transitive inference
No full textAction selection uncertainty in the test phase of a transitive inference task: Neuronal correlates in monkey premotor cortex.
No full textCognitively advanced animals are able to dynamically interact with the environment. In this process, action selection could be strongly influenced by the confidence value assigned to single items in the stream of incoming sensory information.
A form of dynamic representation of the environment is the organization of learned items in hierarchically ordered series. In a 6-items transitive inference task, when the list A > B > C > D > E > F is finally created, the probability of choosing B in the pair BC is lower than for the pair BE suggesting that the confidence for the value of B is variable and related to the mental representation of all other elements presented/experienced together. This relationship between performance and symbol separation is also know as symbolic distance effect.
Previous work has focused on the contribution of sensory information to confidence. We explored how confidence on target value could influence action selection by measuring neuronal activity in the premotor cortex of 2 trained monkeys. We selected neurons with activity modulated by the direction of movement and we analyzed how directionality is influenced by the symbolic distance of items to compare. Our results show that directionality in premotor cortex increases with symbolic distance and uncertainty providing support to the idea that the motor system contributes to perceptual confidence
Logical reasoning in primates: Monkeys’ prefrontal cortex neurons are modulated during manipulation but not during learning of new information
No full text
Subanesthetic doses of NMDA antagoniste ketamine interfere with logically based decision-making in monkeys
No full textAction selection uncertainty in the test phase of a transitive inference task: Neuronal correlates in monkey premotor cortex
No full textCognitively advanced animals are able to dynamically interact with the environment. In this process, action selection could be strongly influenced by the confidence value assigned to single items in the stream of incoming sensory information.
A form of dynamic representation of the environment is the organization of learned items in hierarchically ordered series. In a 6-items transitive inference task, when the list A > B > C > D > E > F is finally created, the probability of choosing B in the pair BC is lower than for the pair BE suggesting that the confidence for the value of B is variable and related to the mental representation of all other elements presented/experienced together. This relationship between performance and symbol separation is also know as symbolic distance effect.
Previous work has focused on the contribution of sensory information to confidence. We explored how confidence on target value could influence action selection by measuring neuronal activity in the premotor cortex of 2 trained monkeys. We selected neurons with activity modulated by the direction of movement and we analyzed how directionality is influenced by the symbolic distance of items to compare. Our results show that directionality in premotor cortex increases with symbolic distance and uncertainty providing support to the idea that the motor system contributes to perceptual confidence
Evaluation of the adjustments of the neural representations of serial ordered items in prefrontal cortex during short practice in a ranks comparison task
No full text- …
