Whole Report
• “report” (remember and write down) as
many letters from a brief display as
possible
• Average in laboratory is 4.5 out of nine
• Class average 2.something
New version of procedure
• Altered procedure: write one row of letters
only—not all of the letters
• “cued” report by saying “top,” “middle,” or
“bottom”
• Actual letters to remember “L” “T” “W”
• With whole report, class average was 2.1 /
9 (~23%)
Performance on new task
• New class average with new procedure
was 2 letters (=2/3 or 67%)
• Huge improvement in performance
• With cue, we seem to “focus on” some of
the letters and ignore others; focusing in
our image of the display (a memory of the
display)
Rapidly fading memory of the
display
• A mental picture (an image) of the display
of letters is created at first
• But, the image only lasts a very short
period of time
• Image lasts long enough to report one row
of letters (about 3 letters), but not long
enough to report all of the letters (9 letters)
Sensory memory
• It’s the rapidly fading image (or memory)
of the display
• “sensory” = tied to your senses
• With vision, it’s called visual sensory
memory (aka, the “icon”)
• Difference in performance between the
original procedure and the modified
procedure (“partial” report) reveals the
existence of sensory memory
Other sensory memories
• One for hearing: audition  auditory
sensory memory (the “echo”)
• Auditory sensory memory only lasts up to
2 seconds
• All sensory memories last for a few
seconds or less
Establishing existence of sensory
memory
• When partial report performance is better
than whole report performance, then that
indicates the presence of sensory memory
• In class demo, partial report (67%) was
higher than whole report (23%), showing
the existence of visual sensory memory
Sperling (1960) experiments
• He established the existence of visual
sensory memory
• Last graph shows that visual sensory
memory lasts for only about ½ second
• The icon is an example of a mental
structure
Attention and the report task
• TLW
• AJQ
• FPO
• Displayed these letters briefly, then cued
report to report one row only
• The cue allows you to select one row and
ignore others (i.e., selective attention)
Kinds of attention
• Selective attention (as in partial report
task): focus on one thing and ignore
another
• Divided attention: trying to pay attention to
more than one thing at a time (i.e.,
multitasking)
Divided Attention
• Serial versus parallel processing
• E.g., two example tasks: taking notes and
mentally planning dinners for each night of
coming week
• One possibility: people have no problem
doing these two things simultaneously
• Means that two separate series of
processing steps occurring at the same
time (called “parallel” processing)
More on divided attention
• If people cannot do the tasks
simultaneously, then not parallel
processing
• One possibility is serial processing (serial
means working on only one thing at a
time)
Potential Causes of serial
processing
• Physical: only have two eyes, only
physically look at one thing at a time, only
have two hands, etc.
• Mental: “interference” between mental
processes, structures, or representations
Mechanisms of interference
• Capacity theory vs. bottleneck theory
• Capacity theory = mind contains a limited
amount of mental resources (kind of like
mental fuel)
• Bottleneck theory = bottleneck in
information processing where only some
information can get through