Ricerc@Sapienza

Deficit in planning and problem-solving, affecting a wide range of neuropsychological patients, has been widely investigated using the Tower of London (ToL) test, as developed by Shallice (Philos Trans R Soc Lond Ser B Biol Sci 298:199-209, 1). The ToL taps on several executive functions (EF), such as planning, time for planning or rule breaks, which may be usefully indexed by different ToL measurements.

We have previously shown how the Frontal Pole cortex (FPC) neurons play a unique role in both the monitoring and evaluating of self-generated decisions during feedback in a visually cued strategy task. For each trial of this task, a cue instructed one of two strategies: to either stay with the previous goal or shift to the alternative goal. Each cue was followed by a delay period, then each choice was followed by a feedback. FPC neurons show goal-selective activity exclusively during the feedback period.

In previous work, we studied the activity of neurons in the dorsolateral (PFdl), orbital (PFo), and polar (PFp) prefrontal cortex
while monkeys performed a strategy task with 2 spatial goals. A cue instructed 1 of 2 strategies in each trial: stay with
the previous goal or shift to the alternative goal. Each trial started with a fixation period, followed by a cue. Subsequently,
a delay period was followed by a “go” signal that instructed the monkeys to choose one goal. After each choice, feedback

The statistical structure of intrinsic parietal and parieto-frontal connectivity in monkeys was studied through hierarchical cluster analysis. Based on their inputs, parietal and frontal areas were grouped into different clusters, including a variable number of areas that in most instances occupied contiguous architectonic fields. Connectivity tended to be stronger locally: that is, within areas of the same cluster. Distant frontal and parietal areas were targeted through connections that in most instances were reciprocal and often of different strength.