Meeting Notes

  • Date: 2025-06-17
  • Time: 09:00 (PT)
  • Location: Teams Meeting
  • Presentations: @Dedalus9 @jeromelecoq @Sarruedi

Agenda

All content should be shared one day prior to the meeting on the linked forum thread (click at the bottom of this page to upload).

  1. SLAP2 analysis data snapshot 1: Nicholas
  2. SLAP2 analysis data snapshot 2: Sarah
  3. Discussion on stimulus design iteration for standard oddball : Jerome and everyone

Meeting Recording

Meeting Notes

Meeting Agenda: Jerome outlined the meeting agenda, which includes presentations by Nicholas, Sarah, and Jerome on various analyses and experimental designs.

Agenda Overview: Jerome outlined the meeting agenda, which includes presentations by Nicholas on population level analysis, Sarah on individual ROI analysis, and Jerome on experimental design variants.

Presentation Details: Jerome mentioned that Nicholas would present analysis on slap two data, Sarah would present her findings, and Jerome would discuss different variants of the experimental design conducted.

Discussion Format: Jerome explained the format of sharing presentations prior to the meeting to facilitate in-depth discussions during the meeting.

Population Level Analysis: Nicholas presented his population level analysis on slap two data, discussing preprocessing steps, tuning preferences, and the impact of photo bleaching on amplitude.

Preprocessing Steps: Nicholas described the preprocessing steps, including normalization by baseline F0 and selection of ROIs based on orientation tuning preference changes after the oddball block presentation.

Photo Bleaching Impact: Nicholas discussed the impact of photo bleaching on amplitude and how he addressed it by focusing on the shape of the ROI tuning vector rather than amplitude.

Tuning Preferences: Nicholas explained how he calculated the tuning spread per ROI and performed min-max scaling to address photo bleaching, focusing on the shape of the ROI tuning vector.

Orientation Tuning: Nicholas explained how he calculated the tuning spread per ROI and performed min-max scaling to address photo bleaching, focusing on the shape of the ROI tuning vector.

Tuning Spread Calculation: Nicholas calculated the tuning spread per ROI by determining the maximum and minimum values for each peristimulus window and retaining ROIs in the top 25% of the tuning spread distribution.

Min-Max Scaling: Nicholas performed ROI-wise min-max scaling to rescale every orientation tuning vector between zero and one per ROI to address photo bleaching.

Orientation Tuning Vector: Nicholas focused on the shape of the ROI tuning vector to mitigate the impact of photo bleaching on amplitude measurements.

Radar Plots: Nicholas shared radar plots to visualize changes in orientation tuning after the presentation of the oddball block, noting patterns of multiple stimuli tuning and dominant tuning changes.

Radar Plot Visualization: Nicholas shared radar plots to visualize changes in orientation tuning after the presentation of the oddball block, noting patterns of multiple stimuli tuning and dominant tuning changes.

Multiple Stimuli Tuning: Nicholas observed that certain ROIs exhibited tuning to multiple stimuli and changed their tuning after the oddball block presentation.

Dominant Tuning Changes: Nicholas noted that some ROIs had one dominant tuning that changed significantly after the oddball block presentation.

PCA Analysis: Nicholas used PCA to analyze changes in orientation tuning vectors, aiming to identify dominant covariance modes and patterns of change across multiple orientations.

PCA Methodology: Nicholas used PCA to compute the cross covariance matrix between pre and post oddball block orientation tuning vectors to identify dominant covariance modes.

Covariance Modes: Nicholas aimed to identify whether changes in orientation tuning vectors exhibited dominant covariance modes focused on single or multiple orientations.

Pattern Analysis: Nicholas analyzed patterns of change across multiple orientations using PCA, noting that changes were not focused on a single orientation but rather across multiple orientations.

Plotting Issues: Lucas and Alexander raised concerns about plotting issues related to orientation angles and the use of direction versus orientation in the analysis.

Orientation Angles: Lucas and Alexander raised concerns about the accuracy of orientation angles in the radar plots, suggesting potential issues with the conversion of direction to orientation angles.

Direction vs Orientation: Lucas and Alexander discussed the difference between direction and orientation angles, highlighting the need to ensure correct computation and plotting in the analysis.

Control Trials: Nicholas emphasized the need for control trials to enable a more robust population level analysis and address potential biases in the PCA process.

Need for Controls: Nicholas emphasized the importance of control trials to enable a more robust population level analysis and address potential biases in the PCA process.

Bias Concerns: Nicholas discussed concerns about potential biases in the PCA process and the need for control trials to mitigate these biases.

Gain Modulation: Sarah presented her analysis on individual ROI level, highlighting a marked gain modulation of synaptic strength in Block 2 compared to Block 1.

Synaptic Strength: Sarah highlighted a marked gain modulation of synaptic strength in Block 2 compared to Block 1, noting that the response amplitude in Block 2 was consistently smaller.

Response Amplitude: Sarah observed that the response amplitude of Delta F/F was almost always smaller in Block 2 compared to Block 1, indicating a gain modulation effect.

Normalization Method: Sarah explained her normalization method, peak normalizing responses to the maximum response across both blocks to illustrate gain changes.

Orientation Selectivity: Sarah discussed the orientation selectivity index for each ROI, noting that while most ROIs remain stable, some exhibit dramatic changes in selectivity.

Selectivity Index: Sarah discussed the orientation selectivity index for each ROI, noting that while most ROIs remain stable, some exhibit dramatic changes in selectivity.

Stable ROIs: Sarah observed that the majority of ROIs remained stable in their orientation selectivity index across blocks.

Dramatic Changes: Sarah noted that some ROIs exhibited dramatic changes in their orientation selectivity index, either losing or gaining selectivity.

Preferred Orientation: Sarah visualized the preferred orientation for each ROI, showing that while many ROIs do not change their preference, some exhibit significant shifts.

Preferred Orientation: Sarah visualized the preferred orientation for each ROI, showing that while many ROIs do not change their preference, some exhibit significant shifts.

Stable Preferences: Sarah noted that many ROIs did not change their preferred orientation across blocks.

Significant Shifts: Sarah observed that some ROIs exhibited significant shifts in their preferred orientation, indicating changes in tuning.

Response Strength: Sarah highlighted the consistent change in response strength across sessions, with many ROIs showing a scaled-down response amplitude in Block 2.

Consistent Change: Sarah highlighted the consistent change in response strength across sessions, with many ROIs showing a scaled-down response amplitude in Block 2.

Scaled-Down Amplitude: Sarah observed that many ROIs showed a scaled-down response amplitude in Block 2 compared to Block 1.

Session Consistency: Sarah noted that the change in response strength was consistent across different sessions, indicating a robust effect.

Receptive Field Mapping: Participants discussed the importance of receptive field mapping as a sanity check and potential internal control for plasticity analysis.

Sanity Check: Participants discussed the importance of receptive field mapping as a sanity check to ensure the accuracy of synaptic input localization.

Plasticity Control: Participants considered receptive field mapping as a potential internal control for analyzing plasticity effects in synaptic inputs.

Experimental Design Variants: Jerome presented several experimental design variants to control for learning effects and contextual modulation, seeking feedback on the most important controls.

Statistical Power Analysis: Lucas and Nicholas agreed to collaborate on statistical power analysis to determine the number of trials needed for reliable measurements in different blocks.