journal article·2025-07-10Open access

Small Language Models for Speech Emotion Recognition in Text and Audio Modalities

José L. Gómez-Sirvent, Francisco López de la Rosa, Daniel Sánchez-Reolid, Roberto Sánchez-Reolid, Antonio Fernández-Caballero

Applied Sciences· Volume 15· Issue 14

Abstract

Speech emotion recognition has become increasingly important in a wide range of applications, driven by the development of large transformer-based natural language processing models. However, the large size of these architectures limits their usability, which has led to a growing interest in smaller models. In this paper, we evaluate nineteen of the most popular small language models for the text and audio modalities for speech emotion recognition on the IEMOCAP dataset. Based on their cross-validation accuracy, the best architectures were selected to create ensemble models to evaluate the effect of combining audio and text, as well as the effect of incorporating contextual information on model performance. The experiments conducted showed a significant increase in accuracy with the inclusion of contextual information and the combination of modalities. The results obtained were highly competitive, outperforming numerous recent approaches. The proposed ensemble model achieved an accuracy of 82.12% on the IEMOCAP dataset, outperforming several recent approaches. These results demonstrate the effectiveness of ensemble methods for improving speech emotion recognition performance, and highlight the feasibility of training multiple small language models on consumer-grade computers.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Emotion and Mood Recognition · Music and Audio Processing · Sentiment Analysis and Opinion Mining

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Instituto de Investigación en Informática de Albacete, Universidad de Castilla-La Mancha, 02071 Albacete, Spain

Departamento de Sistemas Informáticos, Universidad de Castilla-La Mancha, 02071 Albacete, Spain

Departamento de Ingeniería Eléctrica, Electrónica, Automática y Comunicaciones, Universidad de Castilla-La Mancha, 02071 Albacete, Spain

CIBERSAM-ISCIII (Biomedical Research Networking Center in Mental Health, Instituto de Salud Carlos III), 28016 Madrid, Spain

Funding

Spanish MCIU/AEI/10.13039/501100011033/ ERDF, EU · Universidad de Castilla-La Mancha · MICIU/AEI/10.13039/501100011033 · Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (CYTED)

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