# Hedonic hotspot interactions for the generation of 'liking' and 'wanting'

> **NIH NIH F31** · UNIVERSITY OF MICHIGAN AT ANN ARBOR · 2021 · $29,648

## Abstract

PROJECT SUMMARY: The primary role of this proposal is to investigate the corticolimbic circuitry that
controls `liking' reactions to rewards, such as palatable sweet tastes. `Liking', `wanting', and learning are three
distinct components of reward, with distinguishable brain mechanisms, which interact to guide motivated
behavior.1,2 Most research on brain reward mechanisms has traditionally focused on learning and `wanting',
because of the challenges in measuring `liking' in independent ways to identify its neural mechanisms. Yet,
`liking' dysfunction are important components of neuropsychiatric disorders, including depression, and so its
neurobiology is important to understand. One method that has successfully measured `liking' is the affective taste
reactivity test, which measures affective orofacial expressions to various tastes, which are homologous across
various species of animals, and which has identified underlying brain mechanisms.3–5 Studies using measures
of affective `liking' reactions to taste have shown `liking' is controlled by a network of brain hedonic hotspots in
corticolimbic sites including nucleus accumbens, ventral pallidum, orbitofrontal cortex, and insula.6–12 Research
in our lab, including my own, has shown that optogenetically activating the hotspots can amplify `liking'
reactions to the hedonic impact of palatable sucrose reward. 13–16 Activating a hedonic hotspot to amplify `liking'
also recruits Fos expression in the other hedonic hotspots, suggesting they're all simultaneously recruited into
action. 6,17 However, while these hedonic hotspots are thought to mutually recruit and interact to produce `liking'
enhancements, the anatomical projections connecting them have not been identified, as direct projections
between hotspots do not exist 18,19. The current proposal will investigate the indirect anatomical connections
and functional recruitment and interactions within the hedonic hotspot circuitry that amplifies
intense `liking' expressions for palatable rewards. First, the anatomical afferent and efferent projections
of the hedonic hotspots in NAc, VP, insula, and OFC will be identified, using anterograde and retrograde mapping
techniques to identify potential sites of convergence between OFC and NAc hotspots, and between NAc
and VP hotspots. A novel high spatial resolution atlas brain mapping technique will be used in order to
standardize connectivity patterns onto the Swanson rat brain atlas.20–22 The hypothesis that unanimous
recruitment of the hedonic hotspots is necessary for `liking' enhancement will also be tested by activating
one hedonic hotspot and simultaneously disrupting another during taste `liking' reactions. Results from these
experiments will provide insights into the functional circuitry that mediates reward `liking' that may contribute
to understanding various neuropsychiatric disorders. Through the proposed training, I will learn new
techniques, including neuroanatomical projection mapping, brain ...

## Key facts

- **NIH application ID:** 10152758
- **Project number:** 1F31MH125613-01
- **Recipient organization:** UNIVERSITY OF MICHIGAN AT ANN ARBOR
- **Principal Investigator:** Ileana Morales
- **Activity code:** F31 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $29,648
- **Award type:** 1
- **Project period:** 2021-01-01 → 2021-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10152758

## Citation

> US National Institutes of Health, RePORTER application 10152758, Hedonic hotspot interactions for the generation of 'liking' and 'wanting' (1F31MH125613-01). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10152758. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*