Central Executive

The central executive, the most important yet least well understood component of Baddeley's (1986) working memory model, is postulated to be responsible for the selection, initiation, and termination of processing routines (e.g., encoding, storing, retrieving). Baddeley (1986, 1990) equates the central executive with the supervisory attentional system (SAS) described by Norman and Shallice (1980) and by Shallice (1982).

According to Shallice (1982), the supervisory attentional system is a limited capacity system and is used for a variety of purposes, including:

• tasks involving planning or decision making
• trouble shooting in situations in which the automatic processes appear to be running into difficulty
• novel situations
• dangerous or technically difficult situations
• situations where strong habitual responses or temptations are involved

Extensive damage to the frontal lobes may result in impairments in central executive functioning. Baddeley (1986) coined the term dysexecutive syndrome (DES) to describe dysfunctions of the central executive. The classic frontal syndrome is characterized by disturbed attention, increased distractibility, a difficulty in grasping the whole of a complicated state of affairs (Rylander, 1939). In other words, patients suffering from frontal lobe syndrome lack flexibility and the ability to control their processing resources, functions attributed to the central executive.

References:

1. Baddeley, A.D. (1990). Human memory: Theory and practice,. Oxford: Oxford University Press.
2. Baddeley, A.D. (1986). Working memory. Oxford: Clarendon Press.
3. Norman, D.A., & Shallice, T. (1980). Attention to action. Willed and automatic control of behavior. University of California San Diego CHIP Report 99.
4. Shallice, T. (1982). Specific impairments of planning. Philosophical Transactions of the Royal Society London B 298, 199-209.
5. Rylander, G. (1939). Personality changes after operations on the frontal lobes. Acta Psychiatrica Neurologica, Supplement No. 30.

(Revised December 2009)