Optional contemporary study: Darling et al. (2007)

Background and aim

The working memory model has a visuo-spatial sketchpad. Logie (1995) proposed it has two parts: a visual cache (what things look like: form and colour) and an inner scribe (where things are: spatial location and movement). The authors' earlier work with brain-damaged patients suggested that memory for visual appearance and memory for spatial location are held separately.

Aim: to find behavioural evidence for this split in neurologically healthy people.

Method and key idea: double dissociation

The study used selective dual-task interference: participants did a visual appearance memory task or a spatial location memory task while also doing an interference task that loads either the visual or the spatial system. Response times (latency) were measured.

A double dissociation is when interference A disrupts task 1 but not task 2, while interference B disrupts task 2 but not task 1. That pattern shows the two tasks rely on separate systems.

Results, conclusion and evaluation

Results: the abstract reports that the latency data showed an experimental double dissociation between memory for appearance and memory for location (a note in the paper adds that the effect held when age was controlled).

Conclusion: visuo-spatial working memory can be divided into separate subsystems for appearance (visual) and location (spatial), supporting the visual cache and inner scribe idea.

Evaluation: controlled laboratory tasks allow cause and effect and replication; it uses healthy people, which complements patient case studies; but the tasks are artificial (low ecological validity), and dual-task methods assume each interference task loads only one system.

Worked example

Explain what a double dissociation between appearance memory and location memory would look like.

1. Visual interference (for example, watching flickering visual noise) disrupts appearance memory but not location memory.
2. Spatial interference (for example, tapping a pattern) disrupts location memory but not appearance memory.
3. Each interference task affects only one memory task, so the two are separate systems.

Answer: Visual interference harms appearance memory only, and spatial interference harms location memory only.

Check yourself

1. What is a double dissociation?
   • One task disrupts every other task
   • Each of two interference tasks disrupts a different one of two memory tasks
   • Two tasks that never interfere with anything
   • A patient losing STM and LTM together
   Show answer

   Each of two interference tasks disrupts a different one of two memory tasks. Opposite patterns of interference show separate systems.

2. What did Darling et al. conclude?
   • The phonological loop stores visual information
   • The sketchpad is a single store
   • Long-term memory is acoustic
   • Visuo-spatial working memory has separate components for appearance and location
   Show answer

   Visuo-spatial working memory has separate components for appearance and location. Their double dissociation supports separate subsystems.

3. Which part of the visuo-spatial sketchpad (Logie, 1995) stores what objects look like?
   • Inner scribe
   • Visual cache
   • Phonological store
   • Central executive
   Show answer

   Visual cache. The visual cache stores form and colour.

4. What kind of participants did Darling et al. (2007) test?
   • Patients with hippocampal damage
   • Children under five
   • Neurologically healthy people
   • Chimpanzees
   Show answer

   Neurologically healthy people. The point was to find behavioural evidence in healthy people.

5. Which measure did the abstract say showed the dissociation?
   • Latency (response time)
   • Number of words recalled
   • Attractiveness ratings
   • Voltage reached
   Show answer

   Latency (response time). The abstract reports latency data.

6. Give one weakness of using dual-task laboratory experiments like Darling et al. (2007).
   Show answer

   The tasks are artificial, so they lack ecological validity and may not reflect how visuo-spatial memory is used in everyday life.. Artificial tasks and assumptions about pure interference limit the conclusions.

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Sources

• Pearson Edexcel International Advanced Subsidiary/Advanced Level in Psychology specification (issue January 2026)
• Pearson International A Level Psychology component guide: WPS01
• Springer: Darling, Della Sala and Logie (2007) Cognitive Processing 8(3), 175 to 181 (abstract page)
• Simply Psychology: Working memory model

Last updated 8 November 2026. Spotted a mistake? Tell us.