{
"metric": "Change in dopamine neuron firing rate or BOLD signal to unexpected reward",
"papers": [
{
"n": null,
"doi": "10.1016/j.neuron.2005.05.020",
"value": "quantitative match to TD model for positive RPE values",
"cite_key": "Bayer2005",
"study_system": "non-human primate",
"value_source_sentence": "Thus, the firing rate of midbrain dopamine neurons is quantitatively predicted by theoretical descriptions of the reward prediction error signal used in reinforcement learning models for circumstances in which this signal has a positive value."
},
{
"n": 30,
"doi": "10.1038/nature05051",
"value": "significant drug x valence interaction",
"cite_key": "Pessiglione2006",
"study_system": "human",
"value_source_sentence": "L-DOPA boosted subjects' behavioural tendency to choose the most rewarded option, whereas haloperidol reduced this tendency."
},
{
"n": null,
"doi": "10.31887/DCNS.2016.18.1/wschultz",
"value": "comparative effect reported",
"cite_key": "Schultz2016",
"study_system": "rat",
"value_source_sentence": "Most dopamine neurons in the midbrain of humans, monkeys, and rodents signal a reward prediction error; they are activated by more reward than predicted (positive prediction error), remain at baseline activity for fully predicted rewards, and show depressed activity with less reward than predicted (negative prediction error)."
}
],
"n_analyzed": "varies",
"n_definition": "neurons recorded (rodent/NHP) or participants scanned (human)",
"scope_region": "VTA / substantia nigra / ventral striatum",
"comparison_name": "DA neuron firing responses to unexpected reward across species",
"taxonomic_level": "cross-species comparison (rodent, NHP, human)",
"what_it_reveals": "RPE-like signaling is conserved across species but signal characteristics differ",
"scope_population": "midbrain dopamine neurons (rodent/NHP) or striatal BOLD (human)",
"homogeneity_check": {
"overall_verdict": "SPLIT → CAVEAT (resolved) - Restructured as multi-panel figure with separate species panels. Caption caveats required: (1) Metrics are not directly comparable across panels (firing rate vs BOLD); (2) n definitions differ (neurons vs participants); (3) Comparison demonstrates conservation of RPE principle but not quantitative equivalence.",
"n_definition_consistent": "CAVEAT - neuron counts vs participant counts are incommensurable",
"scope_region_consistent": "CAVEAT - rodent/NHP studies record from VTA neurons directly; human studies measure striatal BOLD signal which reflects DA release but also other signals",
"study_system_consistent": "NO - deliberately cross-species comparison",
"scope_population_consistent": "CAVEAT - single-neuron electrophysiology vs bulk fMRI signal are fundamentally different measurements",
"metric_definition_consistent": "NO - firing rate change (spikes/s) cannot be directly compared with BOLD % signal change"
},
"suggested_restructure": "Present as 3 separate panels: (A) NHP single-neuron RPE encoding, (B) Rodent DA neuron RPE, (C) Human striatal BOLD RPE. Panels share x-axis concept (unexpected reward) but y-axis differs per measurement type. Caption must note that cross-species comparison is qualitative."
}