Cognitive Psychology: Connecting Mind, Research and Everyday Experience, 3rd Edition

134 • CHAPTER 5 Short-Term and Working Memory

Articulatory suppression occurs when remembering the second list becomes harder because

repeating “the, the, the.. .” overloads the phonological loop.

Baddeley and coworkers (1984) found that repeating “the, the, the.. .” not only

reduces the ability to remember a list of words, but also eliminates the word length

effect (● Figure 5.17a). According to the word length effect, a list of one-syllable words

should be easier to recall than a list of longer words because the shorter words leave

more space in the phonological loop for rehearsal. However, elimi-

nating rehearsal by saying “the, the, the.. .” eliminates this advan-

tage for short words, so both short and long words are lost from the

phonological store (Figure 5.17b).

THE VISUOSPATIAL SKETCH PAD

The visuospatial sketch pad handles visual and spatial informa-

tion and is therefore involved in the process of visual imagery—the

creation of visual images in the mind in the absence of a physical

visual stimulus. The following demonstration illustrates an early

visual imagery experiment by Roger Shepard and J. Metzler (1971).

DEMONSTRATION Comparing Objects

Look at the two pictures in ● Figure 5.18a and decide, as quickly as pos-

sible, whether they represent two diff erent views of the same object

(“same”) or two diff erent objects (“diff erent”). Also make the same judg-

ment for the two objects in Figure 5.18b.

When Shepard and Metzler measured participants’ reaction

time to decide whether pairs of objects were the same or different,

they obtained the relationship shown in ● Figure 5.19 for objects

that were the same. From this function, we can see that when two

shapes were separated by an orientation difference of 40 degrees

● FIGURE 5.17 (a) Saying “the, the, the.. .” abolishes the word length eff ect, so there is little

diff erence in performance for short words and long words (Baddeley et al., 1984). Saying

“the, the, the.. .” causes this eff ect by reducing rehearsal in the phonological loop.

(a) (b)

Short

words

Long

words

50

Percent correct recall

0

100

Articulatory

suppression

the, the,

the...

Phonological

loop

Visuospatial

sketch pad

Reduces rehearsal

advantage for

short words

● FIGURE 5.18 Stimuli for the “Comparing Objects”

demonstration. (Source: R. N. Shepard & J. Metzler, “Mental Rotation of

Three-Dimensional Objects,” Science, 171, Figures 1a&b, 701–703. Copyright ©

1971 American Association for the Advancement of Science. Reproduced with

permission.)

(a)

(b)

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