logo SBA

ETD

Archivio digitale delle tesi discusse presso l’Università di Pisa

Tesi etd-05062024-112923


Tipo di tesi
Tesi di laurea magistrale
Autore
ANSELMI, MARCO
URN
etd-05062024-112923
Titolo
Design and evaluation of an experimental setup to automatically detect perceived stimuli for psychophysical use
Dipartimento
INGEGNERIA DELL'INFORMAZIONE
Corso di studi
BIONICS ENGINEERING
Relatori
relatore Prof. Micera, Silvestro
tutor Dott. Iberite, Francesco
Parole chiave
  • conscious perception
  • psychophysics
  • pupillometry
  • time-series analysis
Data inizio appello
31/05/2024
Consultabilità
Non consultabile
Data di rilascio
31/05/2094
Riassunto
This thesis investigates the use of pupil behavior to automatically classify stimuli as perceived or not-perceived during psychophysical procedures. Psychophysics traditionally relies on subjective reports, which can be time-consuming and prone to bias. This work proposes a framework using pupil dilation response (PDR) to objectively measure perception.

A custom experimental setup was developed, including a pupillometer, a stimulation device, and software for data acquisition and analysis. The pupillometer uses off-the-shelf components and 3D printing. The stimulation device employs a magnetic linear stepper motor controlled through a custom h-bridge circuit and an Arduino microcontroller.

Experiments were conducted on 10 participants. The results show that the developed system can successfully acquire pupil data and statistically differentiate between perceived and non-perceived stimuli. An ensemble of two k-Nearest Neighbors (KNN) classifiers based on Dynamic Time Warping (DTW) achieved a positive predictive value (PPV) and negative predictive value (NPV) of around 75\% for all participants.

The thesis highlights the potential of pupil behavior analysis for psychophysics. Obtained results suggest that the adopted dynamic approach is suited for PDR analysis and classification. However, limitations exist. The classification performance depends on participant focus and sustained attention. Further research is needed to account for attention and improve classification accuracy.
File