a physical system (see particularly Coltheart, 1980). The mechanism is called "iconic
memory" (Neisser, 1967) or "iconic store." This view corresponds to Coltheart's (1980)
notion of "information persistence."
Much of the dispute can be attributed to some fundamental disagreements with regard to
the procedures used to establish the notion of "iconic store" (Coltheart, 1980) as well as
the converging operations (Garner, Hake, & Eriksen, 1956) used to substantiate some of
the hypothetical properties of the iconic store. The properties in question are its relatively
(with respect to the immediate memory span; Miller, 1956) large storage capacity and the
allegedly "sensory" (in the sense of being precategorical a la Crowder & Morton, 1969)
nature of information representation at the iconic level.
Evidence in support of the iconic store comes generally from the facts that a subject's
partial-report performance is superior to his/her whole-report performance and that such a
superiority declines as the delay of the probe tone in the partial-report task increases
(Sperling, 1960). These observations will jointly be called the "large-capacity finding"
subsequently.
Apart from the dimension of spatial position, other effective partial-report selection
criteria have been identified. They are color (Clark, 1969; Turvey & Kravetz, 1970; von
Wright, 1968), achromatic color (von Wright, 1968), size (von Wright, 1968), and shape
(Turvey & Kravetz, 1970; von Wright, 1968). Category membership (i.e., letters or
digits) is not an effective partial-report selection criterion (Sperling, 1960; von Wright,
1968). In other words, the large-capacity finding is obtained only when the partial-report
selection criterion belongs to a physical ("sensory") dimension. This observation is called
the "basic sensory finding" here.
The first objective of this report is to consider an interesting alternative interpretation of
the "large-capacity
finding" suggested recently by Merikle (1980). The second objective is to reexamine the
basic sensory finding.
EXPERIMENT 1
In order to appreciate Merikle's (1980) argument, it helps to look at Figure 1, in which is
shown a "row display" (top), a "column display" (middle), and a "square display"
(bottom). In terms of the Gestalt principle of spatial proximity, three rows or three
columns may readily be seen when a row or a column display is shown. A square display
is so called because the perceptual gestalt is a square.
Following Kahneman (1973), Merikle (1980) argued that a good gestalt would draw a
perceiver's attention more readily. Consequently, an observer would favor rows and
columns when given row and column displays, respectively. The same observer should