Ralf Haefner

Ralf Haefner

Associate Professor

PhD, Oxford, 1999

Office Location
313 Meliora Hall
Telephone
(585) 276-7453
Web Address

Office Hours: By appointment

Research Overview

My primary scientific interest lies in understanding how the brain forms percepts and how it uses them to make decisions, especially in the visual domain. In particular, I am interested in how the brain's perceptual beliefs about the outside world are represented by the responses of populations of cortical neurons. To that end I use tools from machine learning to construct mathematical models that aim to explain neural responses and behavior.

Research Interests

  • perceptual decision-making
  • probabilistic inference
  • selective attention
  • neural population encoding and decoding
  • depth perception/processing of binocular disparity

Selected Publications

  • Penaloza B, Shivkumar S, Lengyel G, DeAngelis GC, Haefner RM. Causal inference predicts the transition from integration to segmentation in motion perception. Sci Rep. 2024 Nov 12;14(1):27704. . PMID: 39533022; PMCID: PMC11558006.
  • Lange, R.D., Shivkumar, S., Chattoraj, A. et al. Bayesian encoding and decoding as distinct perspectives on neural coding. Nat Neurosci 26, 2063–2072 (2023).
  • Lange RD, Gomez-Laberge C, Berezovskii VK, Plenetev A, Sherdil A, Hartmann T, Haefner RM, Born RT. Weak Evidence for Neural Correlates of Task-Switching in Macaque V1. J Neurophysiol. 2023 Mar 22. . Epub ahead of print. PMID: 36947884.
  • Noel JP, Shivkumar S, Dokka K, Haefner RM, Angelaki DE. Aberrant causal inference and presence of a compensatory mechanism in autism spectrum disorder. Elife. 2022 May 17;11:e71866. .
  • Lange RD, Haefner RM. Task-induced neural covariability as a signature of approximate Bayesian learning and inference. PLoS Comput Biol. 2022 Mar 8;18(3):e1009557. .
  • . A confirmation bias in perceptual decision-making due to hierarchical approximate inference. PLoS Comput Biol. 2021 Nov 29;17(11):e1009517. doi: 10.1371/journal.pcbi.1009517.
  • . Stimulus-dependent relationships between behavioral choice and sensory neural responses. Elife. 2021 Apr 7;10:e54858. doi: 10.7554/eLife.54858. 
  • . Task-uninformative visual stimuli improve auditory spatial discrimination in humans but not the ideal observer. PLoS One. 2019 Sep 9;14(9):e0215417.
  • . Using confidence inferred from pupil-size to dissect perceptual task-strategy: support for a bounded decision-formation process, Journal of Neuroscience 2018, 38 (41) 8874-8888.
  • . Feedback determines the structure of correlated variability in primary visual cortex. Nature Neuroscience. 2018 Feb.
  • . Characterizing and interpreting the influence of internal variables on sensory activity. Curr Opin Neurobiol. 2017 Aug 22;46:84-89. 
  • . Perceptual Decision-Making as Probabilistic Inference by Neural Sampling. Neuron, 90(3):649-60.
  • . Slow Subspace Analysis: A new Algorithm for Invariance Learning, PLoS Computational Biology 10(3):e1003468
  • . Inferring decoding strategies from choice probabilities in the presence of correlated variability. Nature Neuroscience, 16(2), 235–242. doi:10.1038/nn.3309
  • . Evaluating neural codes for inference using Fisher Information, Advances in Information Processing Systems 23, 1993-2001
  • . Push-pull organization of binocular receptive fields robustly encodes disparity in monkey V1, Journal for Neuroscience 31, 22, 8295-8305.
  • . An improved estimator of Variance Explained in the presence of noise, Advances in Information Processing Systems 21, 585-592.
  • . A specialization for the statistics of binocular images in primate V1, Neuron 57, 147-156.
  • . A dynamical model of the inner Galaxy, Monthly Notes of the Royal Astronomical Society 314, 433.
  • . A dynamical model of the inner Galaxy in "Galaxy Dynamics: A Rutgers Symposium", Eds. Merrit, Sellwood, Valluri, 371.
  • . Simple three-integral scale-free galaxy models, Monthly Notes of the Royal Astronomical Society 268, 328.