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Signals derived from the rat motor cortex can be used for controlling one-dimensional movements of a robot arm. It remains unknown, however, whether real-time processing of cortical signals can be employed to reproduce, in a robotic device, the kind of complex arm movements used by primates to reach objects in space. Here we recorded the simultaneous(More)
When an animal learns to make movements in response to different stimuli, changes in activity in the motor cortex seem to accompany and underlie this learning. The precise nature of modifications in cortical motor areas during the initial stages of motor learning, however, is largely unknown. Here we address this issue by chronically recording from neuronal(More)
In simple reaction time tasks, lesions of rat dorsomedial prefrontal cortex impair the ability to wait for trigger stimuli and result in increased premature responding. This effect could be due to impairments in attending to trigger stimuli, estimating the timing of trigger stimuli, or inhibitory control of the motor response. Here, we examined these issues(More)
Muscimol is a GABA A-agonist that causes rapid and reversible suppression of neurophysiological activity. Interpretations of the effects of muscimol infusions into the brain have been limited because of uncertainty about spread of the drug around the injection site. To solve this problem, the present study explored the use of a fluorophore-conjugated(More)
Dorsomedial prefrontal cortex is critical for the temporal control of behavior. Dorsomedial prefrontal cortex might alter neuronal activity in areas such as motor cortex to inhibit temporally inappropriate responses. We tested this hypothesis by recording from neuronal ensembles in rodent dorsomedial prefrontal cortex during a delayed-response task.(More)
In this report we describe how common brain networks within the medial frontal cortex (MFC) facilitate adaptive behavioral control in rodents and humans. We demonstrate that after errors, low-frequency oscillations below 12 Hz are modulated over the midfrontal cortex in humans and within the prelimbic and anterior cingulate regions of the MFC in rats. These(More)
Successful foragers respond flexibly to environmental stimuli. Behavioral flexibility depends on a number of brain areas that send convergent projections to the medial striatum, such as the medial prefrontal cortex, orbital frontal cortex, and amygdala. Here, we tested the hypothesis that neurons in the medial striatum are involved in flexible action(More)
Rats with impaired function in dorsomedial regions of the prefrontal cortex (dmPFC) are unable to maintain a behavioral response over a delay period. Here we report that neurons in this cortical region are prominently modulated after errors in a tone-cued, simple reaction time task and that inactivation of dmPFC attenuates a slowing of reaction times that(More)
We used an operant delayed spatial alternation task to examine the role of rat dorsomedial prefrontal cortex (dmPFC) in spatial working memory. The task was designed to restrict movements during the delay period to minimize use of motor-mediating strategies. Inactivation of dmPFC (muscimol) resulted in increased errors and increased the temporal variability(More)
Many of the cognitive deficits of normal ageing (forgetfulness, distractibility, inflexibility and impaired executive functions) involve prefrontal cortex (PFC) dysfunction. The PFC guides behaviour and thought using working memory, which are essential functions in the information age. Many PFC neurons hold information in working memory through excitatory(More)