Jude Mitchell

  • Address: The Salk Institute, SNL-R, PO Box 85800, San Diego, CA 92186-5800
  • Telephone: (858) 453-4100 x 1499 (email is better)
  • E-mail: jude@salk.edu
  • Curriculum Vitae: [pdf]

  • Research Areas & Aims:
    • How spatial attention alters statistics of neuronal spiking
    • Extracellular classification of neuronal types in awake animals
    • Systems identification models of spiking and neuronal interactions
    • Network models of spiking neurons

  • VSS 2009 Slide Presentation (large file, in pdf format)

  • Cosyne 2009 Slide Presentation (large file, in pdf format)

  • SFN 2008 Poster

  • Sample Matlab Code with V4 Data (Fano Factor, Power Spectra, and Coherence Analyses)

  • Matlab Code for Spike Classification:

  • Attention Task Demo:
    • Multiple-Object Tracking in a Macaque: This video shows the attention-demanding video game that the monkeys performed. The monkeys fixated the white dot at the center of the computer monitor, and four striped stimuli like those in this demonstration, appeared. Their eye position was carefully monitored using a camera. The red cross shows where the eyes were pointing throughout each round of the game. The circle shows the location of the receptive field of the neuron under study on the day that this demonstration was recorded. At the beginning of each round of the game, either one or two of the stimuli were highlighted, indicating to the monkey that they were the targets of attention. The stimuli then moved to new locations and paused, with one stimulus in the receptive field. After a brief pause, they moved to new locations and the fixation point disappeared. The monkey was rewarded with juice if it then looked at the cued targets, proving that they had been tracked. In the latter part of the demonstration, we illustrate neuronal responses from individual rounds of the game. Tick marks indicate when the neuron emitted individual action potentials when the stimulus in the receptive field was tracked (red tick marks) or ignored (blue tick marks).
    • Attention Dask Demo (Avi File)
    • 2nd Demo (run at half-speed)
    • Matlab code to make and show movies

  • Publications:

  • Recent Posters at Conferences:
    • Attention-dependent reductions in response variability in area V4 associated with changes in spike power spectra and burstiness. JF Mitchell, KA Sundberg, and JH Reynolds COSYNE. 2008 [pdf]
    • Sparse reverse correlation sequences improve estimation of V4 neuronal tuning functions. JF Mitchell and JH Reynolds Soc. Neurosci. 2006 [pdf]
    • Attentive tracking of multiple objects modulates neuronal responses in area V4 of macaque. JF Mitchell, KA Sundberg, and JH Reynolds Vision Sci. Soc. 2006 [pdf]
    • Attentive tracking of multiple objects by humans and monkeys. JF Mitchell, KA Sundberg, and JH Reynolds Vision Sci. Soc. 2005 [pdf]
    • Comparison of Human and Macaque Ability to Attentive Track Multiple Visual Stimuli. JF Mitchell, KA Sundberg, and JH Reynolds Soc. Neurosci. 2004 [pdf]
    • Both Motion and Texture Cues Contribute to Object-Based Selection in Binocular Rivalry. JH Reynolds, GR Stoner, and JF Mitchell Soc. Neurosci. 2004 [pdf]

  • Course Information:

  • Other Resources & Matlab Code:
    • Sample Spike-LFP Coherence Data (3 narrow spiking units): ZipFile or Source
    • Saccade Detection Algorithm for I-Scan Eye Position Signals:
    • Algorithm fits the position traces at each time with a parametric sigmoid step function and its derivatives (modeling a discontinuity) or a smooth spline with equal number of free parameters. If the sigmoid fit is 30% better it is considered to be a saccade, as long as the event passes a velocity and acceleration threshold (10deg/s and 100 degs/s^2). Download all files, run "sacanalysis" in Matlab
    • Spike Waveform Classification: ZipFile or Source
    • ISI Distribution Fitting (Single and Dual 'Burst' Process Fits): ZipFile or Source
    • A Neural Model of the Frontal Eye Fields: Source
    • Training Protocol for Rat, version 1.0 (requires psych-toolbox): ZipFile (Matlab code, Run 'ratplay')

  • Neuron and Matlab Code (Older version of code, Summer 2008)