Common coding of expected value and value uncertainty memories in the prefrontal cortex and basal ganglia output

Hikosaka

2022

Nat Commun

Ecological fitness depends on maintaining object histories to guide future interactions. Recent evidence shows that value memory changes passive visual responses to objects in ventrolateral prefrontal cortex (vlPFC) and substantia nigra reticulata (SNr). However, it is not known whether this effect is limited to reward history and if not how cross-domain representations are organized within the same or different neural populations in this corticobasal circuitry. To address this issue, visual responses of the same neurons across appetitive, aversive and novelty domains were recorded in vlPFC and SNr. Results showed that changes in visual responses across domains happened in the same rather than separate populations and were related to salience rather than valence of objects. Furthermore, while SNr preferentially encoded outcome related salience memory, vlPFC encoded salience memory across all domains in a correlated fashion, consistent with its role as an information hub to guide behavior.

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Salience memories formed by value, novelty and aversiveness jointly shape object responses in the prefrontal cortex and basal ganglia

Hikosaka

2022

Nat Commun

“…We used the sessions with largest number of neurons for each of these two regions and merged all different grating conditions. vlPFC (areas 8Av, 46v, and 45) and SNr data are recorded in behaving macaques [42,44] and is available at [78]. The IpN data is from deep cerebellar nucleus of mice [40] and is available at [79].…”

Section: Methodsmentioning

confidence: 99%

“…Next, we checked response variability in another subcortical area namely substantia nigra reticula (SNr). This region was particularly informative for our analysis since here individual neurons showed large dynamic range of excitatory or inhibitory responses to visual objects based on their past value memory (excitation to low value objects and inhibition to high value objects, [42]). Fig 4a and 4b show responses of example neurons to high value and low value objects, respectively.…”

Section: Post-stimulus Enhancement Of Nc Canceling Reduction Of Nrv I...mentioning

confidence: 99%

Stimulus presentation can enhance spiking irregularity across subcortical and cortical regions

Fakharian

2022

PLoS Comput Biol

Self Cite

Stimulus presentation is believed to quench neural response variability as measured by fano-factor (FF). However, the relative contributions of within-trial spike irregularity and trial-to-trial rate variability to FF fluctuations have remained elusive. Here, we introduce a principled approach for accurate estimation of spiking irregularity and rate variability in time for doubly stochastic point processes. Consistent with previous evidence, analysis showed stimulus-induced reduction in rate variability across multiple cortical and subcortical areas. However, unlike what was previously thought, spiking irregularity, was not constant in time but could be enhanced due to factors such as bursting abating the quench in the post-stimulus FF. Simulations confirmed plausibility of a time varying spiking irregularity arising from within and between pool correlations of excitatory and inhibitory neural inputs. By accurate parsing of neural variability, our approach reveals previously unnoticed changes in neural response variability and constrains candidate mechanisms that give rise to observed rate variability and spiking irregularity within brain regions.

“…More specifically, if we focus on the appetitive values of food items, we shall note that this type of subjective value depends on both the internal states of the subjects and their previous experience. Representations of value memory are reported in a couple of temporal and prefrontal cortices as well as in some basal regions in monkeys and humans ( Anderson et al, 2014 ; Kim et al, 2015 ; Ghazizadeh et al, 2020 ; Ghazizadeh and Hikosaka, 2021 ).…”

Section: Introductionmentioning

confidence: 99%

Gustatory Cortex Is Involved in Evidence Accumulation during Food Choice

Ataei

Amini

2022

eNeuro

Self Cite

Food choice is one of the most fundamental and most frequent value-based decisions for all animals including humans. However, the neural circuitry involved in food-based decisions is only recently being addressed. Given the relatively fast dynamics of decision formation, electroencephalography (EEG)-informed fMRI analysis is highly beneficial for localizing this circuitry in humans. Here, by using the EEG correlates of evidence accumulation in a simultaneously recorded EEG-fMRI dataset, we found a significant role for the right temporal-parietal operculum (PO) and medial insula including gustatory cortex (GC) in binary choice between food items. These activations were uncovered by using the “EEG energy” (power 2 of EEG) as the BOLD regressor and were missed if conventional analysis with the EEG signal itself were to be used, in agreement with theoretical predictions for EEG and BOLD relations. No significant positive correlations were found with higher powers of EEG (powers 3 or 4) pointing to specificity and sufficiency of EEG energy as the main correlate of the BOLD response. This finding extends the role of cortical areas traditionally involved in palatability processing to value-based decision-making and offers the “EEG energy” as a key regressor of BOLD response in simultaneous EEG-fMRI designs.