Old/New Recognition Task

Version: v1 (current)

A standard episodic memory paradigm measuring recognition accuracy through old/new judgments and signal detection analysis.

Overview

The Old/New Recognition task is a fundamental paradigm in memory research. Participants first study a list of items (words, images, etc.), then during a test phase, view both studied items ("old") and new items ("new"), making binary recognition judgments for each. This simple design provides rich data on memory accuracy, response bias, and decision criteria through signal detection analysis.

Recognition performance reflects both memory strength (sensitivity/d') and decision strategy (criterion/bias). The task reveals individual differences in memory ability, the effects of encoding strategies, retention intervals, and interference. It's widely used because it requires minimal recall ability, since only a sense of familiarity is needed.

Researchers use this task to study episodic memory, aging, amnesia, false memory, and memory confidence. Clinical applications include dementia screening and memory assessment in neurological disorders.

Scientific Background

Classic Findings:

• Forgetting Curve: Recognition accuracy declines over retention intervals
• Levels of Processing: Deep (semantic) encoding yields better recognition than shallow (perceptual) encoding
• False Recognition: Semantically related lures are often falsely recognized
• Recognition Advantage: Recognition typically easier than free recall
• Confidence-Accuracy Relationship: High-confidence recognition judgments are generally more accurate

Signal Detection Measures:

• d' (d-prime): Sensitivity measure separating memory signal from noise (higher = better discrimination)
• Criterion (c): Response bias (negative = liberal "old" bias, positive = conservative)
• Hit Rate: Proportion of old items correctly recognized
• False Alarm Rate: Proportion of new items incorrectly called old

Seminal Papers:

• Murdock (1962): Serial position effects in free recall and recognition
• Mandler (1980): Recognizing: The judgment of previous occurrence
• Yonelinas (2002): The nature of recollection and familiarity (dual-process theory)

Why Researchers Use This Task

1. Episodic Memory: Measure memory for specific study episodes
2. Memory Assessment: Clinical screening for memory deficits and dementia
3. Aging Research: Track age-related decline in recognition memory
4. False Memory: Investigate conditions that produce false recognition
5. Individual Differences: Assess memory capacity and strategy differences

Configuration Options

Response Mode

Parameter	Type	Default	Description
Time-based trials	boolean	True	If enabled, trials auto-advance after timeout; if disabled, participant responds via button
Use confidence ratings	boolean	False	Collect 1-5 confidence ratings after each old/new judgment

Visual Settings

Parameter	Type	Default	Description
Font size	number	48	Font size for text stimuli (8-400 pixels)

Practice Trials

Parameter	Type	Default	Description
Enable practice	boolean	False	Show practice phase before main study/test
Practice study items	array	[]	Array of items for practice study phase
Practice test trials	array	[]	Array of trials for practice test phase

Keyboard Shortcuts

Researchers can customize the keyboard bindings used during the task:

Parameter	Type	Default	Description
Show keyboard hint	boolean	True	Display an on-screen hint showing the configured keys
Old key	key	O	Key for "old" (previously seen) response
Old action label	text	"Old"	Label shown in the keyboard hint
New key	key	N	Key for "new" (not seen before) response
New action label	text	"New"	Label shown in the keyboard hint

Trial Configuration

Study Phase Configuration

The Study Items spreadsheet defines items to memorize:

Column	Description	Example Values
stimulus	Text content or image URL	Elephant, https://example.com/image.jpg
stimulus_type	Type of stimulus	Text, Image
item_id	Unique identifier for tracking	Word 001, Img 005
block	Optional grouping label	List 1, List 2
fixation_ms	Fixation cross duration before item	500
stimulus_ms	Item presentation duration	2000

Test Phase Configuration

The Test Trials spreadsheet defines recognition test items:

Column	Description	Example Values
stimulus	Text content or image URL	Elephant, https://example.com/image.jpg
stimulus_type	Type of stimulus	Text, Image
item_id	Unique identifier (matches study item for old items)	Word 001, Word New 001
item_status	Whether item was studied	Old, New
block	Optional grouping label	Test 1
fixation_ms	Fixation cross duration before test item	500
stimulus_ms	Response timeout (0 = wait indefinitely)	0, 3000
use_confidence	Override global confidence setting for this trial	True, False

Note: For old items, item_id should match the item_id from the study phase. New items should have unique IDs not present in the study phase.

Example Configuration

Study Items (participants memorize these):

| stimulus  | stimulus_type | item_id   | block  | fixation_ms | stimulus_ms |
|-----------|---------------|-----------|--------|-------------|-------------|
| elephant  | text          | word_001  | list_1 | 500         | 2000        |
| piano     | text          | word_002  | list_1 | 500         | 2000        |
| mountain  | text          | word_003  | list_1 | 500         | 2000        |

Test Trials (mix of old and new):

| stimulus  | stimulus_type | item_id   | item_status | fixation_ms | stimulus_ms |
|-----------|---------------|-----------|-------------|-------------|-------------|
| elephant  | text          | word_001  | old         | 500         | 0           |
| guitar    | text          | new_001   | new         | 500         | 0           |
| piano     | text          | word_002  | old         | 500         | 0           |
| river     | text          | new_002   | new         | 500         | 0           |

Practice Trials

The task supports three practice modes:

• None: Task begins directly with main study/test phases
• Optional: Practice study and test available; participant can skip
• Mandatory: Practice must be completed before main phases

During practice, participants receive visual feedback after each recognition judgment (green checkmark for correct, red X for incorrect).

Participant Experience

Phase Sequence

1. Main Instructions: Overview of the two-phase task structure
2. (Optional) Practice Instructions: If practice enabled
3. (Optional) Practice Study Phase: View practice items
4. (Optional) Practice Test Phase: Make old/new judgments with feedback
5. (Optional) Trials Instructions: Shown before main phases
6. Study Phase Instructions: Brief reminder before study phase
7. Study Phase: View items to memorize
8. Test Phase Instructions: Brief reminder before test phase
9. Test Phase: Make old/new recognition judgments

Study Phase

Each study trial:

• Fixation cross appears (if fixation_ms > 0)
• Item appears (word or image)
• Item displays for specified duration
• Automatic advance to next item

Test Phase

Each test trial:

• Fixation cross appears (if fixation_ms > 0)
• Test item appears
• Participant makes old/new judgment (keyboard or buttons)
• (Optional) If confidence enabled: Select confidence (1-5 scale)
• Visual feedback during practice only

Response Methods

Keyboard (recommended):

• Press O key for "Old" (item was studied) (default -- configurable by researcher)
• Press N key for "New" (item was not studied) (default -- configurable by researcher)
• If confidence enabled: Press 1-5 keys for confidence rating

Buttons (if time-based mode disabled):

• Click "Old" or "New" button
• If confidence enabled: Click confidence rating buttons (1-5)

All keyboard bindings are configurable by the researcher in the study configuration. The keys listed above are the defaults.

Data Output

Markers and Responses

Markers (study_stimulus_shown):

{
  "type": "study_stimulus_shown",
  "ts": "2024-01-01T00:00:01.000Z",
  "hr": 1234.56,
  "data": {
    "item_index": 0,
    "item_id": "word_001",
    "stimulus": "elephant",
    "stimulus_type": "text",
    "block": "list_1"
  }
}

Response Data (test phase):

{
  "trial_index": 0,
  "stimulus_id": "recognition_0_0",
  "item_id": "word_001",
  "source": "keyboard",
  "raw_key": "o",
  "stimulus": "elephant",
  "stimulus_type": "text",
  "item_status": "old",
  "response_value": "old",
  "correct": true,
  "confidence": 5,
  "latency_ms": 1450,
  "ts": "2024-01-01T00:00:02.450Z",
  "hr": 2684.56
}

Summary Artifact

A JSON file (recognition_summary_<taskIndex>.json) with comprehensive statistics including signal detection metrics:

{
  "task_kind": "old_new_recognition",
  "total_trials": 40,
  "signal_detection": {
    "hits": 17,
    "misses": 3,
    "false_alarms": 3,
    "correct_rejections": 17,
    "hit_rate": 0.85,
    "false_alarm_rate": 0.15,
    "d_prime": 2.21,
    "criterion": 0.03
  },
  "overall": {
    "accuracy": 0.85,
    "mean_rt_ms": 1512,
    "mean_correct_rt_ms": 1487
  },
  "confidence_statistics": {
    "mean_confidence": 4.2,
    "confidence_by_accuracy": {
      "correct": 4.5,
      "incorrect": 3.1
    }
  },
  "trials": [ /* per-trial data */ ]
}

Key signal detection metrics:

• d_prime: Sensitivity (ability to distinguish old from new); typical range: 0.5-3.0
• criterion: Response bias; negative = liberal (tend to say "old"), positive = conservative (tend to say "new")
• hit_rate: Proportion of old items correctly identified as old
• false_alarm_rate: Proportion of new items incorrectly identified as old

Instructions

The task uses a six-tier instruction system (expanded for two-phase structure):

1. Main Instructions: Overview shown on dedicated page before task begins
2. Practice Instructions: Shown before practice study phase (if practice enabled)
3. Trials Instructions: Shown before main study phase after practice (if practice enabled)
4. Study Instructions: Brief reminder before study phase begins
5. Test Instructions: Brief reminder before test phase begins
6. Hint Instructions: Quick-reference help available via "?" button during task

All instruction text can be customized in rich-text format during study configuration.

Design Recommendations

List Design

Balanced design (recommended):

• 15-30 study items
• Test phase: 50% old items (from study list) + 50% new items (lures)
• Randomize test order to prevent serial position confounds

Minimum for signal detection analysis:

• 10 old items in study phase
• 10 old + 10 new in test phase (20 total test trials)

Timing Guidelines

Phase	Parameter	Standard	Fast	Slow
Study	Stimulus (ms)	2000ms	1000ms	3000ms
Test	Stimulus (ms)	0 (self-paced)	2000ms	0 (unlimited)

Note: Self-paced testing (stimulus_ms = 0) is most common, allowing participants to respond without time pressure.

Item Selection

For words:

• Match old and new items on word frequency, length, concreteness
• Avoid semantically related lures during initial testing
• Use common, concrete nouns for better encoding

For images:

• Match old and new images on visual complexity, content category
• Ensure new images are not highly similar to studied images
• Use distinctive, memorable images

Practice Configuration

Include practice phase (8-12 items):

• Practice study: 4-6 items
• Practice test: 4-6 old + 4-6 new (8-12 total)
• Provide feedback during practice so participants understand the judgment

Confidence Ratings

When to enable confidence ratings:

• To measure metacognitive accuracy (confidence-accuracy correlation)
• To generate ROC curves for detailed signal detection analysis
• When studying false memory or source confusion

Scale: 1 (not confident) to 5 (very confident)

Retention Interval

The time between study and test can be manipulated:

• Immediate: No delay between study and test (standard)
• Delayed: Insert filler tasks or time delay (10 minutes, 24 hours, etc.)
• Controlled via task sequencing (add tasks between study and test phases)

Common Issues and Solutions

Low Hit Rate (<60%)

Problem: Participants not recognizing studied items

Possible causes:

• Study duration too short
• List too long for memory capacity
• Participants not encoding effectively

Solutions:

• Increase stimulus_ms during study (2500-3000ms)
• Reduce study list length (10-15 items)
• Add encoding task (e.g., rate pleasantness during study)
• Present each item multiple times during study

High False Alarm Rate (>30%)

Problem: Participants incorrectly calling new items "old"

Possible causes:

• New items too similar to studied items
• Liberal response bias
• Confusion about task

Solutions:

• Ensure new items are distinctive from studied items
• Provide clearer instructions emphasizing that new items will appear
• Add practice with feedback to calibrate response bias

Ceiling or Floor Effects

Problem: d' approaching 0 (floor) or 4+ (ceiling)

Solutions for ceiling effects:

• Increase list length (more interference)
• Add retention delay
• Use similar lures (semantically or visually related)

Solutions for floor effects:

• Reduce list length
• Allow multiple study presentations
• Use more distinctive items
• Test immediately (no delay)

Keyboard Responses Not Working

Problem: O and N keys don't register

Solutions:

• Ensure task window has focus (click on task area)
• Check browser compatibility (works best in Chrome/Edge/Firefox)
• Use button-based mode as alternative

Population-Specific Adaptations

Children (8+ years)

• Shorter study lists (8-12 items)
• Slower study pace (3000ms per item)
• Concrete, imageable items (pictures work well)
• Button-based responses may be easier
• Immediate testing (no delay)

Older Adults (65+)

• Slower study pace (2500-3000ms)
• Shorter lists (10-15 items) if memory impaired
• High-frequency, familiar items
• Larger font for text items
• Self-paced testing (no time pressure)
• May show reduced d' and more conservative criterion (normal aging)

Clinical Populations

• Amnesia/Dementia: Very short lists (5-10 items), multiple study presentations, immediate testing
• Yes-bias in dementia: Expect high false alarm rates (liberal criterion)
• Source memory deficits: May recognize items but forget study context
• Adapt based on severity: reduce list length, increase study time, simplify response

References

• Murdock, B. B. (1962). The serial position effect of free recall. Journal of Experimental Psychology, 64(5), 482-488.
• Mandler, G. (1980). Recognizing: The judgment of previous occurrence. Psychological Review, 87(3), 252-271.
• Yonelinas, A. P. (2002). The nature of recollection and familiarity: A review of 30 years of research. Journal of Memory and Language, 46(3), 441-517.
• Snodgrass, J. G., & Corwin, J. (1988). Pragmatics of measuring recognition memory. Journal of Experimental Psychology: General, 117(1), 34-50.

See Also

• DRM False Memory - Related false recognition paradigm
• Lexical Decision - Word familiarity without explicit memory
• Digit Span - Immediate verbal memory capacity