Attention fluctuations impact ongoing maintenance of information in working memory

Area of Science:

• Cognitive Psychology
• Neuroscience

Background:

• Working memory (WM) is crucial for maintaining accessible information.
• WM performance typically degrades with increased retention intervals.
• Previous theories attributed forgetting to reduced precision or sudden memory loss.

Purpose of the Study:

• To investigate the mechanisms underlying working memory decline over time.
• To differentiate between storage capacity and the probability of achieving it.
• To examine the role of attentional control in memory retention.

Main Methods:

• Assessed trial-to-trial performance variations in working memory tasks.
• Utilized two experiments with long (10 s) retention intervals.
• Measured changes in the maximum number of storable items and the probability of achieving this maximum.

Main Results:

• Replicated performance decline after long retention intervals.
• Confirmed forgetting occurs via probabilistic item loss, not all-or-none memory failure.
• Found that maximum storage capacity remained unchanged with longer intervals.
• Identified lower attentional control as the cause for decreased probability of maintaining maximum items.

Conclusions:

• Longer retention intervals impair working memory by reducing the probability of accessing maximum storage capacity.
• Fluctuations in attentional control, not reduced capacity, underlie forgetting over time.
• Working memory stability is compromised by attentional variability during extended retention periods.