Verbal and spatial short-term memory: common sources of developmental change?

Area of Science:

• Cognitive Psychology
• Developmental Psychology
• Neuroscience

Background:

• Short-term memory (STM) capacity is crucial for cognitive development.
• Understanding the factors influencing STM development, particularly in children, is essential.
• Previous research suggests processing speed may play a role in STM capacity.

Purpose of the Study:

• To investigate the age-related and age-invariant components of variance in verbal and spatial short-term memory span.
• To identify the specific cognitive processes contributing to the development of STM span in children.
• To examine the relationship between processing speed, articulation rate, and STM span.

Main Methods:

• Sixty children aged 6 to 12 years participated in the study.
• Participants completed verbal and spatial span tasks, articulation and tapping rate tasks, and speed-of-search tasks.
• Variance-partitioning procedures were employed to analyze the data.

Main Results:

• Age-related variance in both verbal and spatial span was largely explained by speed-of-search and rate predictors.
• Articulation rate contributed independently of age to span performance.
• Task modality did not influence the predictive power of the tasks.
• Steady-state tasks were more predictive than changing-state tasks.

Conclusions:

• Verbal and spatial short-term memory rely on similar underlying processes for serial recall.
• The development of short-term memory span in children is strongly associated with improvements in processing speed.
• Cognitive development in children involves maturational changes in processing speed impacting memory capacity.