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Explores whether 5-month-old infants (N=56) develop numerical- or location-based expectations by using a violation of expectation paradigm with possible and impossible events. Reports that infants use a more abstract representation than object location, the numerical nature of which is discussed. Contains 25 references. (Author/ASK)

The anterior prefrontal cortex (APC) confers on humans the ability to simultaneousLy pursue several goals. How does the brain's motivational system, including the medial frontal cortex (MFC), drive the pursuit of concurrent goals? Using brain imaging, we observed that the left and right MFC, which jointly drive single-task performance according to expected rewards, divide under dual-task conditions: While the left MFC encodes the rewards driving one task, the right MFC concurrently encodes those driving the other task. The same dichotomy was observed in the lateral frontal cortex, whereas the APC combined the rewards driving both tasks. The two frontal lobes thus divide for representing simultaneously two concurrent goals coordinated by the APC. The human frontal function seems limited to driving the pursuit of two concurrent goals simultaneously. 10.1126/science.1183614

The prefrontal cortex (PFC) subserves cognitive control: the ability to coordinate thoughts or actions in relation with internal goals. Its functional architecture, however, remains poorly understood. Using brain imaging in humans, we showed that the lateral PFC is organized as a cascade of executive processes from premotor to anterior PFC regions that control behavior according to stimuli, the present perceptual context, and the temporal episode in which stimuli occur, respectively. The results support an unified modular mode[ of cognitive control that describes the overall functional organization of the human lateral PFC and has basic methodological and theoretical implications., Cognitive control, the ability to coordinate thoughts and actions in relation with internal goals, is often required in our everyday life and subserves higher cognition processes such as planning and [...]

In Experiment 1, participants classified a 1st number (prime) as smaller or larger than 5 and then performed the same task again on a 2nd number (target). In Experiment 2, participants classified a target number as smaller or larger than 5, while unknown to them a masked number was displayed for 66 ms prior to the target. Primes and targets appeared in Arabic notation, in verbal notation, or as random dot patterns. Two forms of priming were analyzed: quantity priming (a decrease in response times with the numerical distance between prime and target) and response priming (faster responses when the prime and target were on the same side of 5 than when they were not). Response priming transferred across notations, whereas quantity priming generally did not. Under conditions of speeded processing, the internal representation of numerical quantities seems to dissociate into multiple notation-specific subsystems.

Distinct dorsal fronto-polar regions are selectively involved in branching processes when compared with other executive processes, according to research designed to identify brain regions involved in both delayed-response and dual-task performance. Functional magnetic resonance imaging was used to demonstrate that bilateral regions in the fronto-polar prefrontal cortex alone are selectively activated when an individual must keep in mind a main aim while undertaking concurrent sub-tasks. Branching-specific regions may play a significant role in processing goal-tree sequences.

Briefly presented and masked visual words may however facilitate the subsequent processing of related words, known as masked priming. Masked primes may activate cognitive processes without access to consciousness. Behavioral and brain-imaging methods were used to estimate the depth of processing of masked numerical primes. Results suggested that masked stimuli have a large influence on electrical and haemodynamic measures of brain activity.

The text describes a model that extends the population coding principles to any multidimensional attribute. The model distinguishes between the distribution of cell activity and the overall activity of a population. The distribution of cell activity is assumed to encode attribute information, while overall activity is assumed to reflect the significance or pertinence of the encoded attribute in the cerebral cortex, according to the dual coding principle. Three basic mechanisms of interaction between the representation of attribute and pertinence are defined and are applied to the motion (MT-MST) cortical pathway in the visual cortex. This framework determines three sources of pertinence that model cognitive processing, including preattentive processing, spatial-selective attention, and object-selective attention. The model accommodates most of the published psychophysical, neurophysiological, and neuroanatomical data and makes several testable predictions about the representations of attribute and enhanced effects in these areas., INTRODUCTION Mental representations can be broken down into separate representations, including visual, auditive, somesthesic, motor representations, or even more abstract representations such as phonological or semantic representations. Neuropsychological and neurophysiological [...]