Antisaccade Task

Field	Value
Name	Antisaccade Task
Version	v0.1.4-dev
URL / Repository	https://github.com/TaskBeacon/T000032-antisaccade
Short Description	Rule-dependent inhibitory control with prosaccade versus antisaccade responses.
Created By	TaskBeacon
Date Updated	2026-03-18
PsyFlow Version	0.1.12
PsychoPy Version	2025.1.1
Modality	Behavior
Language	Chinese
Voice Name	zh-CN-YunyangNeural (voice disabled by default)

1. Task Overview

This task implements a two-condition antisaccade paradigm:

• prosaccade: respond toward the target side.
• antisaccade: respond opposite the target side.

Each logical trial presents a fixation baseline, a rule cue, a short gap, and a lateralized target response window. The build uses keyboard direction keys (f/j) as a portable proxy for gaze direction.

The task no longer uses a separate controller object. Trial-specific rule, target-side, and timing values are generated by a deterministic helper in src/utils.py from the block seed and trial id, which keeps the runtime auditable without maintaining cross-trial mutable state.

2. Task Flow

Block-Level Flow

Step	Description
1. Block setup	Load the block condition stream with BlockUnit.generate_conditions(...) and resolve the per-block seed.
2. Trial execution	Run fixation -> rule cue -> gap -> saccade response -> ITI for each logical trial.
3. Block summary	Summarize only logical trial rows from the completed block and show accuracy, correct RT, and timeout count.
4. Final summary	Show session-level totals and save the reduced CSV output.

Trial-Level Flow

Step	Description
fixation	Show center fixation and left/right peripheral anchors.
rule_cue	Present condition cue (朝圆点 or 背离圆点).
gap	Remove cue and keep neutral anchors before target onset.
saccade_response	Present one lateral target and capture left/right response under deadline.
iti	Show neutral fixation scene until next trial.

Helper Logic

Component	Description
Rule parser	Validates prosaccade vs antisaccade and rejects unknown labels.
Deterministic spec builder	Samples target side from a stable seed basis (block_seed + trial_id) and computes the correct key.
Summary helpers	Aggregate reduced rows into accuracy, mean correct RT, timeout count, and total trials.

Controller Logic

Component	Description
Task-local controller	Not used. Deterministic helper logic in src/utils.py replaces mutable controller state.

Runtime Context Phases

Phase Label	Meaning
fixation	Neutral baseline before the rule cue.
rule_cue	Rule preparation period.
gap	Cue-target separation interval.
saccade_response	Active response capture window.
iti	Inter-trial reset interval.

3. Configuration Summary

a. Subject Info

Field	Meaning
subject_id	3-digit participant identifier.

b. Window Settings

Parameter	Value
size	[1280, 720]
units	pix
screen	0
bg_color	gray
fullscreen	false
monitor_width_cm	35.5
monitor_distance_cm	60

c. Stimuli

Stimulus Group	Description
fixation	Central fixation cross used in fixation/gap/ITI phases.
rule_pro, rule_anti	Color-coded rule cues (朝圆点, 背离圆点).
left_anchor, right_anchor	Peripheral position anchors shown before target onset.
left_target, right_target	Lateral white target circles for directional response.
instruction_text, block_break, good_bye	Entry, transition, and completion text screens.

d. Timing

Stage	Duration
fixation	uniform in fixation_duration range
rule cue	uniform in cue_duration range
gap	uniform in gap_duration range
response window	response_deadline
ITI	iti_duration

e. Helper Logic

Helper	Purpose
src/utils.py	Deterministic trial-spec generation and summary aggregation.
task.enable_logging	Enables the helper to emit auditable trial-spec logging.

f. Triggers

Trigger	Code	Semantics
exp_onset	1	experiment start
exp_end	2	experiment end
block_onset	10	block start
block_end	11	block end
fixation_onset	20	fixation onset
rule_pro_onset	21	prosaccade rule cue onset
rule_anti_onset	22	antisaccade rule cue onset
gap_onset	30	gap onset
target_onset_left	40	left target onset
target_onset_right	41	right target onset
response_left	50	left response key
response_right	51	right response key
response_timeout	60	no response before deadline
iti_onset	70	inter-trial interval onset

4. Methods (for academic publication)

Participants completed a rule-based oculomotor inhibition task containing prosaccade and antisaccade trials. Each trial began with fixation, followed by an explicit rule cue and a short cue-target gap, then a lateral target requiring a directional response. Prosaccade trials required same-side responses relative to target location; antisaccade trials required opposite-side responses.

Behavioral outputs were logged at trial level, including condition, target side, response key, correctness, reaction time, and timeout status. The implementation emits phase-aligned triggers for fixation, cue, gap, target onset, response category, and ITI to support synchronized acquisition workflows.