# Neural and behavioral mechanisms of olfactory generalization in the human brain

> **NIH NIH F31** · NORTHWESTERN UNIVERSITY · 2020 · $45,520

## Abstract

SUMMARY
A critically important feature of the brain is the ability to generalize from previously encountered stimuli
to new stimuli. Generalization allows the brain to reduce computational demands that would otherwise
be necessary to create unique representations for each and every encounter, while enabling animals to
deal with the complexity of real-world situations. Stimulus generalization is a fundamental cognitive
mechanism that underlies adaptive behavior. While generalization reduces the necessity of learning the
associative value of every stimulus we encounter, equally important is the ability to distinguish
perceptually related stimuli that hold different meanings. The neural mechanisms underlying the shift
from discrimination learning to generalization remain poorly understood. The research proposed here
aims to examine olfactory fear generalization and discrimination on multiple levels. In Aim 1 I will use a
novel functional MRI (fMRI) paradigm of olfactory aversive conditioning to associate odor cues with an
aversive outcome to explore the behavioral, physiological, and neural mechanisms underlying olfactory
generalization. Then, in Aim 2 I will use repetitive transcranial magnetic stimulation (rTMS) techniques
to modulate olfactory generalization gradients to identify the specific functional roles of brain regions
involved in generalization. The research proposed here will help delineate the neural and behavioral
underpinnings of odor generalization in limbic brain areas (hippocampus, amygdala, orbitofrontal
cortex, and piriform cortex) known to be involved in regulation of emotion and decision-making. Thus,
findings emerging from my project could inform future translational studies in patients with anxiety or
post-traumatic stress disorder (PTSD) whose symptoms may arise from disruptions of stimulus
generalization, and may help direct new treatments or insights into diagnosis and prognosis.

## Key facts

- **NIH application ID:** 9986740
- **Project number:** 5F31DC017062-03
- **Recipient organization:** NORTHWESTERN UNIVERSITY
- **Principal Investigator:** Daria Porter
- **Activity code:** F31 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $45,520
- **Award type:** 5
- **Project period:** 2018-09-01 → 2021-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9986740

## Citation

> US National Institutes of Health, RePORTER application 9986740, Neural and behavioral mechanisms of olfactory generalization in the human brain (5F31DC017062-03). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/9986740. Licensed CC0.

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