Theories Inattentional blindness

1 theories

1.1 perceptual load
1.2 inattentional amnesia
1.3 expectation
1.4 perceptual cycle

theories
perceptual load

this particular hypothesis bridges gap between , late selection theories. authors integrate viewpoint of selection stating perception limited process (i.e. cognitive resources limited), , of late selection theories assuming perception automatic process. view proposes level of processing occurs 1 stimulus dependent on current perceptual load. is, if current task attentionally demanding , processing exhausts available resources, little remains available process other non-target stimuli in visual field. alternatively, if processing requires small amount of attentional resources, perceptual load low , attention inescapably directed non-target stimuli.

the effects of perceptual load on occurrence of inattentional blindness demonstrated in study fougnie , marois. here, participants asked complete memory task involving either simple maintenance of verbal stimuli, or rearrangement of material, more cognitively demanding exercise. while subjects completing assigned task, unexpected visual stimulus presented. results revealed unexpected stimuli more missed during manipulation of information in more simple rehearsal task.

in similar type of study, fmri recordings done while subjects took part in either low-demand or high-demand subtraction tasks. while performing these exercises, novel visual distractors presented. when task demands low , used smaller portion of finite resources, distractors captured attention , sparked visual analysis shown brain activation in primary visual cortex. these results, however, did not hold when perceptual load high; in condition, distractors less attended , processed.

thus, higher perceptual load, , therefore more significant use of attentional resources, appears increase likelihood of inattentional blindness episodes.

inattentional amnesia

the theory of inattentional amnesia provides alternative in explanation of inattentional blindness in suggesting phenomenon not stem failures in capture of attention or in actual perception of stimuli, instead failure in memory. unnoticed stimuli in visual scene attended , consciously perceived, rapidly forgotten rendering them impossible report. in essence, inattentional amnesia refers failure in creating lasting explicit memory: time subject asked recall seeing item, memory stimulus has vanished.

while difficult tease apart failure in perception 1 in memory, research has attempted shed light on issue. in now-classic study of inattentional blindness, woman carrying umbrella through scene goes unnoticed. despite stopping video while walking through , asking participants identify of 2 people have seen – leaving little delay possible between presentation , report – observers fail correctly identify woman umbrella. no differences in performance identified whether video stopped after unexpected event or moments later. these findings seem oppose idea of inattentional amnesia, advocates of theory contend memory test came late , memory had been lost.

expectation

the phenomenon of inattentional blindness defined lack of expectation unattended stimulus. researchers believe not inattention produces blindness, in fact aforementioned lack of expectation stimuli. proponents of theory state classic methods testing inattentional blindness not manipulating attention per se, instead expectation presentation of visual item.

studies investigating effect of expectation on episodes of inattentional blindness have shown once observers made aware of importance of stimuli presented, example stating 1 later tested on it, phenomenon disappears. while admitting possible ambiguities in methodology, mack, 1 of foremost researchers in field, holds inattentional blindness stems predominantly failure of attentional capture. points out if expectation not mediate instances of closely linked phenomena such attentional blink , change blindness (whereby participants have difficulty identifying changing object when explicitly told it), unlikely inattentional blindness can explained solely lack of expectation stimulus presentation.

perceptual cycle

the perceptual cycle framework has been used theoretical basis inattentional blindness. perceptual cycle framework describes attention capture , awareness capture occurring @ 2 different stages of processing. attention capture occurs when there shift in attention due salience of stimuli, , awareness capture refers conscious acknowledgement of stimuli. attentional sets important because composed of characteristics of stimuli individual processing. inattentional blindness occurs when there interaction between individual s attentional set , salience of unexpected stimulus. recognizing unexpected stimulus can occur when characteristics of unexpected stimulus resembles characteristics of perceived stimuli. attentional set theory of inattentional blindness has implications false memories , eyewitness testimony. perceptual cycle framework offers 4 major implications inattentional blindness 1) environmental cues aid in detection of stimuli providing orienting cues not enough produce awareness, 2) perception requires effortful sustained attention, interpretation, , reinterpretation, 3) implicit memory may precede conscious perception, , 4) visual stimuli not expected, explored, or interpreted may not perceived.

other bases attentional blindness include top down , bottom processing.