Working Memory Model Notes

Lecture 10: The Working Memory Model

Introduction

  • Overview of memory models

    • Previous model: Atkinson and Shiffrin (1968)

    • Inadequacies of the modal model, leading to the proposal of a new model by Alan Baddeley.

  • Baddeley’s working memory model:

    • Accommodates data fitting/modal model and data that does not.

    • Makes new predictions and allows theoretical modifications.

  • Focus of this lecture: Examination of Baddeley’s working memory model and related research.

Baddeley’s Working Memory Model

  • Unitary Memory Store Perspective:

    • Assumes a single memory storage place (long-term store).

    • Working memory is not a storage module; rather a set of processing modules interacting with long-term memory.

Components of Working Memory Model

  • Central Executive:

    • Higher-level component associated with consciously directed activities.

    • Functions include:

    • Goal-directed retrieval of information from long-term memory.

    • Manipulation of retrieved information for tasks (e.g., mathematical calculations, drawing inferences).

    • Evaluative functions with outcomes registering in long-term memory store.

    • Direct activation of stored meanings for comparative evaluations (e.g., size comparisons).

    • Ability to recode information across formats (e.g., from image to sound).

    • Integrative processes supporting chunking, binding elements into larger meaningful wholes.

    • Cognitive Resource Allocation:

    • Directs attentional resources toward other contents and activities.

    • Not merely a memory mechanism but an attentional one.

  • Activation Buffers: Two subordinate buffers supporting the Central Executive:

    • Phonological Loop:

    • Also called articulatory loop, keeps a limited number of speech sounds activated.

    • Utilizes the process of subvocal rehearsal (silent repetition of sounds).

    • Visuospatial Sketchpad:

    • Maintains a limited number of visual patterns actively available.

    • Suspected rehearsal process analog to phonological loop (no special name).

    • Both activation buffers referred to as slave systems; serve the central executive’s higher-order functions and have dedicated cognitive pools.

Resource Allocation in Buffers

  • Central Executive’s ability to allocate additional resources for challenging tasks when buffers reach capacity limits.

  • Buffers maintain information from long-term store active for executive manipulations.

Empirical Studies Supporting Baddeley’s Model

  • Phonological Loop Studies:

    • Baddeley, Thomson, and Buchanan (1975) Experiments:

    • Investigated the word length effect through three experiments assessing phonological loop validity.

    1. Experiment 1:

      • Immediate recall of word lists varying in length and syllables.

      • Results demonstrated better recall for short lists and shorter syllable words – confirming the phonological loop’s function.

    2. Experiment 4:

      • Manipulated average spoken duration of words (less than half a second vs. close to one second).

      • Results showed better recall for shorter duration words (72.2%) compared to longer words (61.6%).

    3. Experiment 7:

      • Investigated recall of visually presented words with and without engaging in an articulatory suppression task.

      • Control condition showed typical word-length effect; this effect eliminated in the presence of articulatory suppression task, supporting phonological loop’s function.

  • Visuospatial Sketchpad Studies:

    • Lee Brooks (1968) Trials:

    • Participants held a visual stimulus (block letter F) while answering Yes/No questions based on stimulus characteristics.

    • Two response modes: spatial and verbal;

    • Results indicated that spatial response mode impaired performance when holding visual patterns in the sketchpad, providing evidence for separate processing of visual and spatial information.

    • Della Sala et al. (1999) Study:

    • Participants performed a visual grid-shading task or spatial Corsi blocks task with interference tasks varying in nature.

    • Results supported the independence of visual and spatial rehearsal mechanisms, with distinct interference effects noted for different tasks.

Resource Borrowing

  • Baddeley and Hitch (1974) Study on Resources:

    • Participants engaged in a statement verification task varying difficulty of processing statements and articulatory suppression tasks.

    • Results indicated that more difficult tasks required greater attentional resources, impacting accuracy and response times, especially when articulatory suppression increased demands.

Working Memory as an Attentional Mechanism

  • Baddeley’s concept suggests that working memory should not be perceived as a distinct memory store but rather as processes enabling the activation and transformation of long-term memories through strategic allocation of attention.

Mental Chronometry and Scanning Working Memory

  • Mental Chronometry: The study of time requirements for cognitive processes.

    • Subtractive Method (Franciscus Donders, 1868):

    • Procedure requiring comparison of task performance times to isolate time for specific cognitive functions based on task composition.

    • Additive Method (Saul Sternberg):

    • Proposed method whereby repeated task performance measures additional time required for mental processes, applied to scanning contents in working memory.

    • Sternberg’s study (1969): Examined scanning of working memory contents through immediate memory scanning tasks demonstrating exhaustive serial scanning behavior in response times, indicating all items are examined even after a match.

Working Memory Span and Related Studies

  • Working Memory Span Task (Daneman and Carpenter):

    • Developed measure contrasting traditional digit span tasks with verbal materials.

    • Findings demonstrated correlation between working memory span and pronoun reference comprehension tasks.

    • Strong correlation with SAT scores, indicating importance of working memory in academic performance.

  • Alternative Working Memory Span Task (Engle):

    • Participants engaged in sentence-word pairs recall task emphasizing both retrieval of components and comprehension.

    • Span scores considered as fixed attributes prior to experimental conditions, leading to diverse cognitive performance studies.

Key Empirical Studies on Working Memory Span

  • Conway, Cowan, and Bunting (2001):

    • Examined attentional focus using dichotic listening tasks revealing high vs. low memory span’s ability to maintain focus.

  • Kane and Engle’s Proactive Interference Studies (2000, 2003):

    • Compared interference effects between groups, emphasizing attentional differences.

  • Rosen and Engle (1997) Verbal Fluency Task:

    • Assessed generation of animal names under attention-demanding conditions demonstrating the disparity in strategic vs. automatic processing among memory spans.

Conclusion

  • Working memory is largely indicative of attentional focus and functionality in cognitive tasks, not merely as a memory store.

  • The ability of working memory as a mechanism for accessing long-term memory through attentional resource allocation is a significant area of interest for cognitive psychology, highlighting its broad implications across cognitive tasks and academic performance.