Forward frontal fields: phylogeny and fundamental function

“They contribute to prospective coding[41,42]; sensory working memory[43,44]; attention to objects, places, actions and intentions[36, 45 ,46]; response inhibition[47]; the categorization of objects, sounds and event sequences[48‐50]; the selection, generation and sequencing of multiple actions[51‐53]; problemsolving s…”

“Research on the ‘granular’ prefrontal cortex of humans emphasizes such processes as updating, manipulating and strategic controlofinformationstoredinshort-termmemory[33, 67 ]; establishingtasksetsandrules[68];mediatinghierarchies of behavioral control; behavioral inhibition; cognitive control in social situations[69];…”

“Neurophysiological results that had been interpreted as memory signals[ 35 ]enabled other interpretations, usually because crucial variables remained uncontrolled and often unmonitored.”

“The idea that the knowledge stored by the ‘granular’ prefrontal cortex concerns aspects of behavior agrees with previous proposals about its role in behavioral flexibility and the diversity of its cognitive contributions, as propounded for example by Duncan and colleagues[72, 73 ,75]and by Shallice and Norman[76,77]as…”

“They contribute to prospective coding[41,42]; sensory working memory[ 43 ,44]; attention to objects, places, actions and intentions[36,45,46]; response inhibition[47]; the categorization of objects, sounds and event sequences[48‐50]; the selection, generation and sequencing of multiple actions[51‐53]; problemsolving s…”

“The idea that the knowledge stored by the ‘granular’ prefrontal cortex concerns aspects of behavior agrees with previous proposals about its role in behavioral flexibility and the diversity of its cognitive contributions, as propounded for example by Duncan and colleagues[72,73,75]and by Shallice and Norman[ 76 ,77]as…”

“They contribute to prospective coding[41,42]; sensory working memory[43,44]; attention to objects, places, actions and intentions[36,45, 46 ]; response inhibition[47]; the categorization of objects, sounds and event sequences[48‐50]; the selection, generation and sequencing of multiple actions[51‐53]; problemsolving s…”

“Figure adapted, with permission, from Ref.[27]for part (a), Ref.[26]for part (b), Ref.[ 24 ]for part (c) and Ref.[25]for part (d).”

“These concepts include the preparatory set for future actions, in addition to processing events across time gaps[58‐60], decision making[ 61 ]and goal selection[62].”

“Orbital areas seem to function more in value- and object-based action selection[ 65 ,66].”

“(Please note that the letter ‘a’ has two meanings: in Ia it means agranular; in 13a it distinguishes that area from area 13b.) Architectonics are taken from Ref.[ 20 ]for part (i), Ref.[21]”

“The idea that the knowledge stored by the ‘granular’ prefrontal cortex concerns aspects of behavior agrees with previous proposals about its role in behavioral flexibility and the diversity of its cognitive contributions, as propounded for example by Duncan and colleagues[ 72 ,73,75]and by Shallice and Norman[76,77]as…”

“Figure adapted, with permission, from Ref.[ 27 ]for part (a), Ref.[26]for part (b), Ref.[24]for part (c) and Ref.[25]for part (d).”

“Here, I take up that topic first, and at heart it involves a fundamental question: what is the prefrontal cortex? The second topic concerns the distinction between cognitive processes and knowledge, and it involves a similarly fundamental question: what does the prefrontal cortex do? Grafman and colleagues[ 2 ] have n…”

“striatum, targeting more dorsal parts of the striatum instead[23,25, 26 ].”

“The shared frontal areas For the rest of the story see Preuss[ 8 ,9], but an argument based on cortical types, topology and corticostriatal organization should suffice.”

“striatum, targeting more dorsal parts of the striatum instead[23, 25 ,26].”

“Neuroimaging[33,37‐39]and other[ 40 ]research in humans yield the same conclusion.”

“Two are especially useful in my opinion: one based mainly on neuroimaging and clinical neuropsychology, the other on neurophysiology and neuroanatomy[2, 29 ].”

“They contribute to prospective coding[ 41 ,42]; sensory working memory[43,44]; attention to objects, places, actions and intentions[36,45,46]; response inhibition[47]; the categorization of objects, sounds and event sequences[48‐50]; the selection, generation and sequencing of multiple actions[51‐53]; problemsolving s…”

“Also included are the ideas emphasized in contemporary neuroeconomics[ 63 ]such as reward expectation, the valuation and revaluation of actions and stimuli, and the effect of reinforcement history on decisions, choices and actions.”

“In another test of spatial memory, rats returned to normal performance just 60 trials after medial frontal lesions[ 19 ].”

“Petrides[ 34 ]did an especially crucial experiment in macaque monkeys.”

“They contribute to prospective coding[41,42]; sensory working memory[43, 44 ]; attention to objects, places, actions and intentions[36,45,46]; response inhibition[47]; the categorization of objects, sounds and event sequences[48‐50]; the selection, generation and sequencing of multiple actions[51‐53]; problemsolving s…”

“highest activity when the monkey remembered the R location (top row), regardless of where the monkey attended (columns).(c)Most cells in the dorsolateral prefrontal cortex are like the blue one in B. Data from Ref.[ 36 ].”

“By contrast, rats trained after medial frontal lesions reached 90% correct performance at a median interval of 2 s, and they did so in just 140 trials: a respectable, if subpar, achievement[ 18 ].”

“Monkeys trained after prefrontal lesions failed to learn the DR task at all, even after 500 trials with a brief 1-s interval[ 17 ].”

“This task, thus, required the processes invoked by several theories of the ‘granular’ prefrontal cortex: the maintenance of information in working memory[71], adaptive coding, which confers the ability to guide behavior whenever problems exceed routine levels of difficulty[72,73], and attentional selection[37,74], inc…”

“In a study that used a 5-s delay interval, two of four monkeys performed at chance level for 1000 trials, when testing stopped[ 15 ].”

“They contribute to prospective coding[41,42]; sensory working memory[43,44]; attention to objects, places, actions and intentions[36,45,46]; response inhibition[47]; the categorization of objects, sounds and event sequences[48‐50]; the selection, generation and sequencing of multiple actions[51‐53]; problemsolving str…”

“Although some experts held more nuanced views, very few studies tested the working-memory theory of prefrontal cortex critically, and one that did contradicted it fairly convincingly[ 30 ].”

“This task, thus, required the processes invoked by several theories of the ‘granular’ prefrontal cortex: the maintenance of information in working memory[71], adaptive coding, which confers the ability to guide behavior whenever problems exceed routine levels of difficulty[72,73], and attentional selection[ 37 ,74], i…”

“In accord with this idea, neuroanatomists have recognized a ‘ventral shift’ of corticostriatal projections (from a given area) in primates relative to rodents[ 28 ].”

“Specifically, neuroimaging experiments pitting attentional selection against the maintenance of information in working memory showed a predominance of attentional functions for the dorsolateral prefrontal cortex [32], and other studies also stressed attentional functions, such as monitoring items in short-term memory[…”

“Orbital areas seem to function more in value- and object-based action selection[65, 66 ].”

“Neuroimaging studies at first emphasized working memory, then other ideas began to intrude[ 31 ].”

“In the spirit of e pluribus unum, the strategy task (Figure 6a) that we devised might help us to understand how several kinds of knowledge combine to produce a sophisticated behavior[54, 62 ,70].”

“Research on the ‘granular’ prefrontal cortex of humans emphasizes such processes as updating, manipulating and strategic controlofinformationstoredinshort-termmemory[33,67]; establishingtasksetsandrules[68];mediatinghierarchies of behavioral control; behavioral inhibition; cognitive control in social situations[ 69 ];…”

“Research on the ‘granular’ prefrontal cortex of humans emphasizes such processes as updating, manipulating and strategic controlofinformationstoredinshort-termmemory[33,67]; establishingtasksetsandrules[ 68 ];mediatinghierarchies of behavioral control; behavioral inhibition; cognitive control in social situations[69];…”

“They contribute to prospective coding[41, 42 ]; sensory working memory[43,44]; attention to objects, places, actions and intentions[36,45,46]; response inhibition[47]; the categorization of objects, sounds and event sequences[48‐50]; the selection, generation and sequencing of multiple actions[51‐53]; problemsolving s…”

“They contribute to prospective coding[41,42]; sensory working memory[43,44]; attention to objects, places, actions and intentions[36,45,46]; response inhibition[ 47 ]; the categorization of objects, sounds and event sequences[48‐50]; the selection, generation and sequencing of multiple actions[51‐53]; problemsolving s…”

“This complete failure persisted in subsequent testing with 2-s intervals [ 16 ].”

“In the spirit of e pluribus unum, the strategy task (Figure 6a) that we devised might help us to understand how several kinds of knowledge combine to produce a sophisticated behavior[54,62, 70 ].”

“…(Figure 7A), a region that has been implicated in cognitive functions such as attentional search, working memory, cognitive control, and decision making between motivational outcomes (Williams and Castner, 2006; Lee and Seo, 2007; Wise, 2008; Kable and Glimcher, 2009; Wallis and Kennerley, 2010).”

“Dorsolateral prefrontal cortex, a key component of the cognitive workspace, is lacking in most other mammals, and is less developed in nonhuman primates than in humans (Reep, 1984; Braak, 1980; Preuss, 1995; Wise, 2008).”