Functions of the anterior insula in taste, autonomic, and related functions

A non-reward attractor theory of depression

“…Indeed, the orbitofrontal cortex has the inputs and representations required to compute nonreward, namely representations of expected value, and reward and punishment outcome value (Rolls, 2014a;Rolls and Grabenhorst, 2008), and it is not clear that the subgenual cingulate cortex has the information to perform that computation. (Similar arguments apply to the anterior insula, which is also implicated in autonomic function (Rolls, 2015a), though it has also been described as part of a "salience network" (Menon and Uddin, 2010). Insular as well as anterior cingulate metabolism have been found to predict the successful outcome of treatment in depression (Fu et al, 2013;McGrath et al, 2013).)…”

“…The orbitofrontal cortex projects to the supracallosal anterior cingulate cortex which is involved in learning and correcting actions in relation to non-reward and punishment; and to the anterior insula and subgenual cingulate cortex which are involved inter alia in autonomic responses (Rolls, 2015a) which become altered in depression. The orbitofrontal cortex also projects to the amygdala, and to the basal ganglia which may be involved in habit (stimulus-response) learning (Rolls, 2014a).…”

“…Because the lateral orbitofrontal cortex responds to many punishing and non-rewarding stimuli (Grabenhorst and Rolls, 2011;Rolls, 2014a, b) that are likely to elicit autonomic/visceral responses, as does the supracallosal anterior cingulate cortex, and in view of connections from these areas to the anterior insula which is implicated in autonomic/visceral function (Critchley and Harrison, 2013;Rolls, 2015a), the anterior insula would also be expected to be overactive in depression, and that prediction is confirmed (Drevets, 2007;Hamilton et al, 2013;Ma, 2015).…”

“…In addition to the lateral orbitofrontal cortex and two regions that receive inputs from it, the insula implicated in autonomic functions (Rolls, 2015a), and the supracallosal anterior cingulate cortex, which are all activated by unpleasant stimuli (Grabenhorst and Rolls, 2011;Rolls, 2014a), parts of the amygdala are activated by unpleasant stimuli, and parts by pleasant stimuli (Rolls, 2014a), and amygdala activity has been related to depression (Harmer and Cowen, 2013;Ma, 2015;Price and Drevets, 2012). However, the amygdala is less involved in non-reward, especially the rule-based reversal of which stimuli are classified as rewarding that is required in a rapid reward reversal task (Rolls, 2014a).…”

Non-reward neural mechanisms in the orbitofrontal cortex

“…Reward Outcome is represented in the orbitofrontal cortex by its neurons that respond to taste and fat texture (Rolls, Yaxley and Sienkiewicz 1990, Rolls and Baylis 1994, Rolls, Critchley, Browning, Hernadi and Lenard 1999, Verhagen, Rolls and Kadohisa 2003, Rolls, Verhagen and Kadohisa 2003b, and do this based on their reward value as shown by the fact that their responses decrease to zero when the reward is devalued by feeding to satiety (Rolls, Sienkiewicz and Yaxley 1989, Rolls, Critchley, Browning, Hernadi and Lenard 1999, Rolls 2015b, Rolls 2016c. Moreover, the primate orbitofrontal cortex is key in these reward value representations, for it receives the necessary inputs from the inferior temporal visual cortex, insular taste cortex, and pyriform olfactory cortex, yet in these preceding areas reward value is not represented (Rolls 2014, Rolls 2015b, Rolls 2015a. There is consistent evidence that Expected Value and Reward Outcome Value are represented in the human orbitofrontal cortex (O'Doherty, Kringelbach, Rolls, Hornak and Andrews 2001, Rolls, O'Doherty, Kringelbach, Francis, Bowtell and McGlone 2003a, Kringelbach, O'Doherty, Rolls and Andrews 2003, Rolls, McCabe and Redoute 2008, Grabenhorst, Rolls and Bilderbeck 2008, Rolls 2014, Rolls 2015b.…”