https://doi.org/10.5061/dryad.c2fqz61kb

Experiment Description

The dataset was collected in experiments where monkeys performed a passive object-association task designed to study learning dynamics. All details can be found in the methods section of the manuscript (https://www.biorxiv.org/content/10.1101/2023.04.24.538054v1).

Experiment 1

In the first experiment, the monkeys were presented with visual stimuli consisting of a colour and a shape. The reward was determined by a nonlinear combination (XOR) of these features. Neural recordings were collected from the very first session to capture the learning process as it unfolded.

Experiment 2

In the second experiment, an additional pair of colours was introduced to assess whether the rule learned in the first experiment could generalise to a new sensory domain.

In both experiments:

• The second object presented had two features:
  • Shape: Relevant for reward prediction.
  • Width: Irrelevant to reward prediction.
• The trial sequence was randomized.
• Trials with fixation errors were excluded from the dataset.

Files and variables

Each .zip file in this repository corresponds to one experimental session for a specific animal. The naming convention for these files is as follows:

• Example: m1ses24.zip
  • m1 denotes Monkey 1.
  • ses24 stands for Session 24.

Each .zip file contains three .npy files, which provide detailed information about the session:

1. Data: Contains smoothed firing rates in the format of n_trials × n_neurons × 250_timepoints.
2. Electrode Location (cell_loc): Indicates the brain area where each neuron’s activity was recorded.
3. Trial Information (meta): Provides a vector of integers corresponding to the trial identities in the data file.

Electrode Location Coding (cell_loc)

The electrode locations are coded as follows:

• 1: Dorsal to Principal Sulcus (dlPFC)
• 2: Dorsal Principal Sulcus
• 3: Ventral Principal Sulcus
• 4: Ventral to Principal Sulcus (vlPFC)
• 5: Lateral Orbitofrontal Cortex (lateral OFC)
• 6: Beyond Superior Arcuate Sulcus
• 7: Beyond Inferior Arcuate Sulcus

Trial Information Coding (meta)

The meta file contains trial identities, coded as integers that correspond to the trials in the data file. The coding differs slightly between Experiment 1 and Experiment 2.

Experiment 1

• 1: Colour 1, Shape 1, Width 1, XOR 1 (Reward)
• 2: Colour 1, Shape 1, Width 0, XOR 1 (Reward)
• 3: Colour 1, Shape 2, Width 1, XOR 0 (No Reward)
• 4: Colour 1, Shape 2, Width 0, XOR 0 (No Reward)
• 5: Colour 2, Shape 1, Width 1, XOR 0 (No Reward)
• 6: Colour 2, Shape 1, Width 0, XOR 0 (No Reward)
• 7: Colour 2, Shape 2, Width 1, XOR 1 (Reward)
• 8: Colour 2, Shape 2, Width 0, XOR 1 (Reward)

Experiment 2

• 1: Colour 1, Shape 1, Width 1, XOR 1 (Reward)
• 2: Colour 1, Shape 1, Width 0, XOR 1 (Reward)
• 3: Colour 1, Shape 2, Width 1, XOR 0 (No Reward)
• 4: Colour 1, Shape 2, Width 0, XOR 0 (No Reward)
• 5: Colour 2, Shape 1, Width 1, XOR 0 (No Reward)
• 6: Colour 2, Shape 1, Width 0, XOR 0 (No Reward)
• 7: Colour 2, Shape 2, Width 1, XOR 1 (Reward)
• 8: Colour 2, Shape 2, Width 0, XOR 1 (Reward)
• 9: Colour 3, Shape 1, Width 1, XOR 1 (Reward)
• 10: Colour 3, Shape 1, Width 0, XOR 1 (Reward)
• 11: Colour 3, Shape 2, Width 1, XOR 0 (No Reward)
• 12: Colour 3, Shape 2, Width 0, XOR 0 (No Reward)
• 13: Colour 4, Shape 1, Width 1, XOR 0 (No Reward)
• 14: Colour 4, Shape 1, Width 0, XOR 0 (No Reward)
• 15: Colour 4, Shape 2, Width 1, XOR 1 (Reward)
• 16: Colour 4, Shape 2, Width 0, XOR 1 (Reward)

Data File Format

• Data Shape: The data array is structured as n_trials × n_neurons × 250_timepoints.
• Timepoints: Each trial consists of 250 timepoints representing the smoothed firing rates.
  • Colour Display: The colour stimulus was presented between timepoints 50 and 150.
  • Shape and Width Display: The shape and width features were presented between timepoints 100 and 150.
  • Reward Delivery: The reward was delivered at timepoint 150.