# Response Inhibition Task (RIT) - Complete Specification Document

## 1. Test Overview

### 1.1 Definition
The Response Inhibition Task (Go/No-Go Task) measures an individual's ability to suppress automatic, dominant, or prepotent responses when they are inappropriate. It evaluates impulse control and the capacity to resist distractions or temptations.

### 1.2 Core Cognitive Ability Measured
- **Response Inhibition**: Capacity to stop oneself from responding impulsively
- **Impulse Control**: Ability to hold back automatic reactions
- **Attention Control**: Maintaining focus and following rules

### 1.3 Test Structure Overview
```
Practice Phase: 7 trials (with feedback)
Main Test: 75 trials across 3 blocks (no feedback)
Total: 82 trials
Duration: ~10-12 minutes
```

---

## 2. Age Group Specifications

### 2.1 Adolescents (14-18 years)

**Stimuli:**
- Magic Potion 🧪 (image file)
- Bomb 💣 (image file)

**Response Window:**
- 2.5 seconds per trial

**Language Style:**
- Casual, encouraging, game-like
- Examples: "Great job!", "Let's go!", "challenge", "game"

**Thematic Design:**
- Treasure/magic theme
- Colorful, engaging visuals
- Fun, motivating atmosphere

### 2.2 Adults (18-22 years)

**Stimuli:**
- Red Circle (solid color)
- Blue Circle (solid color)

**Response Window:**
- 2.0 seconds per trial

**Language Style:**
- Formal, concise, clinical
- Examples: "Proceed", "Complete", "task", "trial"

**Thematic Design:**
- Professional, research-oriented
- Clean, minimal visuals
- Clinical atmosphere

---

## 3. Test Phases

### 3.1 Practice Phase

**Purpose:**
- Familiarize participants with task mechanics
- Teach stimulus-response mapping
- Allow learning without performance pressure

**Structure:**
```
Trials: 7
Feedback: YES (after every trial)
Reversals: NOT applicable
Goal: Learn the basic rules
```

**Practice Trial Sequences:**

Adolescents:
```javascript
Trial 1: Bomb (No-Go)
Trial 2: Potion (Go)
Trial 3: Potion (Go)
Trial 4: Bomb (No-Go)
Trial 5: Potion (Go)
Trial 6: Bomb (No-Go)
Trial 7: Potion (Go)
```

Adults:
```javascript
Trial 1: Red (Go)
Trial 2: Blue (No-Go)
Trial 3: Red (Go)
Trial 4: Red (Go)
Trial 5: Blue (No-Go)
Trial 6: Blue (No-Go)
Trial 7: Red (Go)
```

### 3.2 Main Test Phase

**Purpose:**
- Measure actual response inhibition performance
- Test cognitive flexibility through rule switching
- Assess adaptation to changing demands

**Structure:**
```
Blocks: 3
Trials per Block: 25
Total Trials: 75
Feedback: NO (only blue highlight on response)
Reversals: Rules switch in Block 2, return in Block 3
```

**Block Breakdown:**
```
Block 1: Trials 1-25 (Original rules)
Block 2: Trials 26-50 (REVERSED rules)
Block 3: Trials 51-75 (Back to original rules)
```

---

## 4. Block Structure & Rule Switching

### 4.1 Block 1 - Baseline Establishment

**Purpose:** Establish prepotent response pattern

**Adolescents Rules:**
- **GO:** Tap when you see Potion 🧪
- **NO-GO:** Don't tap when you see Bomb 💣

**Adults Rules:**
- **GO:** Tap when you see Red Circle
- **NO-GO:** Don't tap when you see Blue Circle

**Trial Distribution:**
- 15 Go trials (60%)
- 10 No-Go trials (40%)

**Goal:** Create automatic habit of responding to one stimulus

### 4.2 Block 2 - Rule Reversal

**Purpose:** Test cognitive flexibility and inhibition under interference

**Adolescents Rules (REVERSED):**
- **GO:** Tap when you see Bomb 💣
- **NO-GO:** Don't tap when you see Potion 🧪

**Adults Rules (REVERSED):**
- **GO:** Tap when you see Blue Circle
- **NO-GO:** Don't tap when you see Red Circle

**Trial Distribution:**
- 15 Go trials (60%)
- 10 No-Go trials (40%)

**Challenge:** Override established habit from Block 1

### 4.3 Block 3 - Return to Original

**Purpose:** Test re-adaptation and measure interference effects

**Rules:** Same as Block 1 (Original rules restored)

**Trial Distribution:**
- 15 Go trials (60%)
- 10 No-Go trials (40%)

**Challenge:** Switch back after learning reversed pattern

---

## 5. Trial Types

### 5.1 Go Trials (60% of trials)

**Definition:** Trials requiring an active response

**Expected Action:** Press key/click screen

**Correct Response:**
- Participant responds within time window
- Score: 1 (correct)

**Incorrect Response:**
- Participant fails to respond (timeout)
- Classification: **Omission Error**
- Score: 0 (incorrect)

**Example:**
```
Adolescent Block 1: See Potion → Should tap
Adult Block 1: See Red → Should tap
```

### 5.2 No-Go Trials (40% of trials)

**Definition:** Trials requiring response inhibition

**Expected Action:** Do NOT press key/click screen

**Correct Response:**
- Participant withholds response (inhibits successfully)
- Score: 1 (correct)

**Incorrect Response:**
- Participant responds when shouldn't
- Classification: **Commission Error** (False Alarm)
- Score: 0 (incorrect)

**Example:**
```
Adolescent Block 1: See Bomb → Should NOT tap
Adult Block 1: See Blue → Should NOT tap
```

---

## 6. Timing Specifications

### 6.1 Trial Timing Flow

**Complete Trial Sequence:**
```
1. Fixation Cross: 0.3 seconds
2. Stimulus Display: 2.5s (adolescent) / 2.0s (adult)
3. Feedback (practice only): 1.0s or 1.5s
4. Inter-Trial Interval: 0.3 seconds
```

**Total per Trial:**
- Practice: ~5-6 seconds
- Main Test: ~3-4 seconds

### 6.2 Phase Durations

**Fixation Cross:**
- Duration: 300ms
- Purpose: Alert participant to prepare
- Display: "+" symbol centered

**Stimulus Presentation:**
- Adolescents: 2,500ms
- Adults: 2,000ms
- Purpose: Response window
- Behavior: Accept responses during this window only

**Feedback Display (Practice Only):**
- Correct responses: 1,000ms
- Incorrect responses: 1,500ms
- Purpose: Learning reinforcement

**Inter-Trial Interval:**
- Duration: 300ms
- Purpose: Brief pause between trials
- Display: Blank screen

### 6.3 Timeout Handling

**When Stimulus Window Expires:**
```
1. Cancel stimulus display
2. Show "Time is up!" message
3. Display for 1 second
4. Record trial result:
   - Go trial → Omission Error (incorrect)
   - No-Go trial → Correct Inhibition (correct)
5. Proceed to next trial
```

---

## 7. Response Handling

### 7.1 Response Methods

**Accepted Inputs:**
- Spacebar key press
- Mouse click anywhere on screen
- Touch tap (mobile devices)

**Response Detection:**
- Active only during stimulus display window
- Ignored during fixation and inter-trial intervals

### 7.2 Response Confirmation

**Visual Feedback:**
- Blue outline/ring appears immediately on response
- Remains visible for duration of stimulus display
- No other feedback during main test

**Timeout Response:**
- "Time is up!" message displays for 1 second
- Participant receives no other indication

---

## 8. Feedback Rules (Practice Phase Only)

### 8.1 Correct Go Response

**Trigger:** Participant pressed when they should

**Message:** "Good job! You pressed at the right time."

**Duration:** 1.0 second

**Purpose:** Reinforce correct active response

### 8.2 Missed Go Response (Omission Error)

**Trigger:** Participant didn't press when they should

**Message:** "Remember to press when you see the Go picture!"

**Duration:** 1.5 seconds

**Optional:** Gentle alert tone

**Purpose:** Remind to respond to Go stimuli

### 8.3 Incorrect No-Go Response (Commission Error)

**Trigger:** Participant pressed when they shouldn't

**Message:** "Try not to press when you see the No-Go picture."

**Duration:** 1.5 seconds

**Purpose:** Reinforce inhibition requirement

### 8.4 Correct No-Go Response

**Trigger:** Participant successfully inhibited response

**Message:** "Great! You stopped at the right time."

**Duration:** 1.0 second

**Purpose:** Reinforce successful inhibition

### 8.5 Inactivity Alert

**Trigger:** No response within 1.5s (adults) or 2s (adolescents) of stimulus onset

**Message:** "Please respond quickly!"

**Duration:** 1.0 second

**Audio:** "Beep" tone plays

**Purpose:** Encourage faster responding

**Note:** This is distinct from timeout - it's a mid-trial warning

---

## 9. Main Test Differences

### 9.1 No Feedback Display

**During Main Test:**
- No verbal feedback messages shown
- No correctness indication
- No performance updates

**Only Visual Confirmation:**
- Blue highlight on response (shows action was registered)
- "Time is up!" on timeout

**Purpose:** 
- Measure performance without learning aid
- Reduce anxiety about errors
- Focus on natural response patterns

### 9.2 Block Instructions

**When Displayed:**
- Before Block 1 starts
- Before Block 2 starts (after Block 1 completion)
- Before Block 3 starts (after Block 2 completion)

**Content:**
- Current block number
- Rule explanation
- Reminder of task goals
- "Let's Go!" button to begin

---

## 10. Trial Sequences (Exact Order)

### 10.1 Block 1 Trial Order - Adolescents

```
Trial 1-25:
Bomb(N), Potion(G), Potion(G), Bomb(N), Potion(G),
Potion(G), Bomb(N), Bomb(N), Potion(G), Potion(G),
Potion(G), Potion(G), Bomb(N), Potion(G), Bomb(N),
Potion(G), Potion(G), Bomb(N), Potion(G), Bomb(N),
Potion(G), Potion(G), Bomb(N), Potion(G), Bomb(N)

G = Go trial, N = No-Go trial
Total: 15 Go, 10 No-Go
```

### 10.2 Block 2 Trial Order - Adolescents

```
Trial 26-50:
Bomb(G), Potion(N), Bomb(G), Bomb(G), Potion(N),
Bomb(G), Potion(N), Potion(N), Bomb(G), Bomb(G),
Bomb(G), Potion(N), Bomb(G), Bomb(G), Potion(N),
Bomb(G), Potion(N), Bomb(G), Bomb(G), Potion(N),
Bomb(G), Potion(N), Bomb(G), Bomb(G), Potion(N)

Rules REVERSED: Bomb=Go, Potion=No-Go
Total: 15 Go, 10 No-Go
```

### 10.3 Block 3 Trial Order - Adolescents

```
Trial 51-75:
Bomb(N), Potion(G), Potion(G), Bomb(N), Potion(G),
Bomb(N), Potion(G), Potion(G), Bomb(N), Potion(G),
Bomb(N), Potion(G), Bomb(N), Potion(G), Potion(G),
Bomb(N), Potion(G), Bomb(N), Potion(G), Potion(G),
Bomb(N), Potion(G), Bomb(N), Potion(G), Potion(G)

Rules BACK TO ORIGINAL: Potion=Go, Bomb=No-Go
Total: 15 Go, 10 No-Go
```

### 10.4 Block 1 Trial Order - Adults

```
Trial 1-25:
Red(G), Blue(N), Red(G), Red(G), Red(G),
Red(G), Blue(N), Blue(N), Red(G), Red(G),
Blue(N), Red(G), Blue(N), Red(G), Blue(N),
Red(G), Red(G), Blue(N), Red(G), Blue(N),
Red(G), Red(G), Blue(N), Red(G), Blue(N)

G = Go trial, N = No-Go trial
Total: 15 Go, 10 No-Go
```

### 10.5 Block 2 Trial Order - Adults

```
Trial 26-50:
Blue(G), Red(N), Blue(G), Blue(G), Red(N),
Blue(G), Red(N), Red(N), Blue(G), Blue(G),
Blue(G), Red(N), Blue(G), Blue(G), Red(N),
Blue(G), Red(N), Blue(G), Blue(G), Red(N),
Blue(G), Red(N), Blue(G), Blue(G), Red(N)

Rules REVERSED: Blue=Go, Red=No-Go
Total: 15 Go, 10 No-Go
```

### 10.6 Block 3 Trial Order - Adults

```
Trial 51-75:
Blue(N), Red(G), Red(G), Blue(N), Red(G),
Red(G), Red(G), Blue(N), Blue(N), Red(G),
Red(G), Blue(N), Red(G), Blue(N), Red(G),
Red(G), Blue(N), Red(G), Blue(N), Red(G),
Red(G), Blue(N), Red(G), Blue(N), Red(G)

Rules BACK TO ORIGINAL: Red=Go, Blue=No-Go
Total: 15 Go, 10 No-Go
```

---

## 11. Scoring and Accuracy

### 11.1 Trial Scoring Logic

**Go Trial Scoring:**
```javascript
if (trialType === 'go') {
  if (responded) → score = 1 (correct)
  if (!responded) → score = 0 (omission error)
}
```

**No-Go Trial Scoring:**
```javascript
if (trialType === 'no-go') {
  if (responded) → score = 0 (commission error)
  if (!responded) → score = 1 (correct inhibition)
}
```

### 11.2 Accuracy Metrics

**Overall Accuracy:**
```
(Total Correct Responses / Total Trials) × 100
```

**Go Trials Accuracy:**
```
(Correct Go Responses / Total Go Trials) × 100
```

**No-Go Trials Accuracy:**
```
(Correct No-Go Responses / Total No-Go Trials) × 100
```

**Hit Rate:**
```
(Correct Go Responses / Total Go Trials) × 100
Same as Go Trials Accuracy
```

---

## 12. Error Classification

### 12.1 Commission Errors (False Alarms)

**Definition:** Responding when should inhibit

**When It Occurs:**
- No-Go trial + participant responds

**Significance:**
- Primary measure of response inhibition failure
- Higher count = poorer impulse control

**Commission Error Rate:**
```
(Commission Errors / Total No-Go Trials) × 100
```

### 12.2 Omission Errors

**Definition:** Failing to respond when should

**When It Occurs:**
- Go trial + participant doesn't respond (timeout)

**Significance:**
- Indicates inattention or slow processing
- Can result from being too cautious

**Omission Error Rate:**
```
(Omission Errors / Total Go Trials) × 100
```

---

## 13. Reaction Time Metrics

### 13.1 Response Time Recording

**When RT is Recorded:**
- Only when participant makes a response
- Measured from stimulus onset to response action
- Recorded in milliseconds

**RT Not Recorded When:**
- No response given (timeout)
- Response outside stimulus window

### 13.2 RT Calculations

**Go Trials Mean RT:**
```
Average RT for all correct Go trial responses
Excludes omission errors (no RT to average)
```

**No-Go Trials Mean RT:**
```
Average RT for commission errors only
Shows how quickly participant made inhibition failures
```

**Overall Task Mean RT:**
```
Average RT across all responses
Includes both correct Go and commission errors
```

**RT Interpretation:**
- Faster Go RT = better processing speed
- Faster No-Go RT on errors = impulsive responding
- Slower Go RT = cautious/careful approach

---

## 14. Data Recording Structure

### 14.1 Per-Trial Data

**Essential Fields:**
```javascript
{
  trialNumber: 1-82,
  phase: 'practice' | 'main',
  blockNumber: 0 | 1 | 2 | 'practice',
  trialInBlock: 1-25,
  stimulus: 'potion' | 'bomb' | 'red' | 'blue',
  trialType: 'go' | 'no-go',
  currentRule: "description",
  participantResponse: 'responded' | 'no-response' | 'timeout',
  responseTime: number | null,
  responseAccuracy: 0 | 1,
  feedbackShown: string | null,
  timestamp: number
}
```

### 14.2 Summary Statistics

**Performance Metrics:**
- Total Trials: 75 (main test)
- Total Correct: Sum of all correct responses
- Total Incorrect: Sum of all errors
- Overall Accuracy %
- Hit Rate %
- False Alarm Rate %

**Error Counts:**
- Commission Errors: Total count
- Omission Errors: Total count
- Commission Error Rate %
- Omission Error Rate %

**Timing Metrics:**
- Mean Go RT
- Mean No-Go RT (commission errors)
- Overall Mean RT
- Fastest RT
- Slowest RT

---

## 15. Instructions Text

### 15.1 Generic Instructions (Both Groups)

"In this game, you'll see simple symbols appear on the screen. Your job is to react quickly when the rules tell you to tap, and to hold back when the rules say not to tap. The rules may change as you go, so stay focused and be ready to adjust. Let's begin!"

"Before the main game starts, you'll do a few practice rounds to get familiar with the task. Try to respond quickly and correctly!"

"Each time you see a plus sign (+), get ready and pay close attention for the next round."

### 15.2 Practice Instructions - Adolescents

"In this practice round, tap the screen as fast as you can when you see a Potion 🧪, and don't tap when you see a Bomb 💣. Try to respond quickly and correctly — let's see how well you can follow the rules!"

"When you feel set to take on the challenge, tap 'Let's Go!' below and the game begins!"

### 15.3 Practice Instructions - Adults

"In this practice round, tap the screen when you see a Red circle, and don't tap when you see a Blue circle. Respond quickly and accurately to learn the task!"

"When you're prepared to begin the task, press 'Let's Go!' below to start."

### 15.4 Practice Complete - Adolescents

"Great job finishing the practice! Now get ready for the real task. Tap 'Let's Go!' below and the game begins!"

### 15.5 Practice Complete - Adults

"Great job finishing the practice! Now get ready for the real task. Tap 'Let's Go!' below and the game begins!"

---

## 16. Block-Specific Instructions

### 16.1 Block 1 Instructions - Adolescents

"Welcome! In this game, you'll see two designs appear — a magic potion 🧪 or a bomb 💣.
• If you see a potion 🧪, tap it as fast as you can.
• If you see a bomb 💣, don't touch the screen.
• You'll need to react quickly.
• Stay sharp! Sometimes you'll need to act, and sometimes you'll need to stop yourself.
• There are three rounds. Let's begin the first one — good luck!"

### 16.2 Block 1 Instructions - Adults

"Welcome! This is a quick reaction game. You'll see a red circle or a blue circle appear.
• If it's red, tap it fast.
• If it's blue, don't tap.
• You won't have much time, so react quickly before the game moves on.
• There are three rounds — let's start with the first one!"

### 16.3 Block 2 Instructions - Adolescents

"Great job! Now the rules are changing.
• This time, if you see a bomb 💣, you must tap it fast.
• If you see a potion 🧪, don't tap.
• Keep your focus — the game is trickier now!"

### 16.4 Block 2 Instructions - Adults

"Nice work on Round 1! The rules are changing now.
• If it's blue, tap it fast.
• If it's red, don't tap.
• Stay alert."

### 16.5 Block 3 Instructions - Adolescents

"Final round! The rules are back to how they were at the beginning.
• Tap for potion 🧪, don't tap for bomb 💣.
• Play carefully and finish strong!"

### 16.6 Block 3 Instructions - Adults

"Final round! We're going back to the first rule.
• Tap when you see red.
• Don't tap when you see blue.
• Be quick and accurate to finish strong!"

---

## 17. Completion Messages

### 17.1 Task Complete - Adolescents

"Awesome work! You've completed this challenge — stay sharp, the next one is coming up!"

### 17.2 Task Complete - Adults

"Well done! You've successfully finished this task — let's move on to the next part."

---

## 18. Key Behavioral Measures

### 18.1 Response Inhibition Capacity

**Measured By:** No-Go trial accuracy

**Interpretation:**
- High accuracy = strong inhibition ability
- Low accuracy = weak impulse control
- Commission errors indicate failures

### 18.2 Cognitive Flexibility

**Measured By:** Performance change across blocks

**Interpretation:**
- Block 2 accuracy drop = difficulty adapting
- Block 3 recovery = good flexibility
- Persistent errors = rigid thinking

### 18.3 Processing Speed

**Measured By:** Mean reaction time on Go trials

**Interpretation:**
- Faster RT = quicker processing
- Very fast RT with errors = impulsive
- Slow RT = cautious approach

### 18.4 Sustained Attention

**Measured By:** Consistency across trials and blocks

**Interpretation:**
- Stable accuracy = good attention
- Declining accuracy = attention fatigue
- Omission errors = attention lapses

---

## 19. Clinical Relevance

### 19.1 Applications

**Research Areas:**
- ADHD assessment
- Impulse control disorders
- Executive function evaluation
- Cognitive development studies
- Neuropsychological assessment

**What It Reveals:**
- Ability to suppress automatic responses
- Adaptation to changing rules
- Attention maintenance
- Processing speed under time pressure

### 19.2 Performance Patterns

**Healthy Performance:**
- High Go trial accuracy (>90%)
- Moderate-high No-Go accuracy (>75%)
- Quick Go trial RT (~400-600ms)
- Good adaptation in Block 2

**Impaired Inhibition:**
- High commission errors (>30%)
- Fast RT on commission errors
- Difficulty in Block 2 and 3
- Inconsistent performance

**Attention Issues:**
- High omission errors
- Variable RT
- Declining accuracy over time
- Similar errors across all blocks

---

## 20. Test Validity Requirements

### 20.1 Administration Standards

**Must Follow:**
- Exact trial sequences from specification
- Precise timing for each phase
- Consistent instructions
- No interruptions during test

**Must NOT:**
- Provide hints or coaching
- Show performance during main test
- Allow breaks mid-block
- Modify trial order or timing

### 20.2 Data Quality Indicators

**Valid Test Administration:**
- All 82 trials completed
- No technical errors recorded
- Response times within plausible range (100-2500ms)
- No extended pauses between trials

**Invalid Data Flags:**
- Participant not paying attention
- Technical failures
- Interruptions during test
- RT patterns suggest random responding

---

This completes the comprehensive specification of the Response Inhibition Task, covering all essential details for accurate understanding and implementation of the test protocol.