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this is related to vigilance performance
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Gaurav Kumar Rai and Indramani L. Singh
Cognitive Science Laboratory
Department of Psychology
Banaras Hindu University, Varanasi-221005
Email ID: [email protected], [email protected]
Respiration and Body Temperature as Measures of Sustained Attention: an
Empirical Evidence
A state of readinessto detect andrespond to a smallchanges occurringat random timeintervals overprolongedperiods.
Per
form
an
ce
Time period
?
Cognitive Science Laboratory, BHU
Determinant of Vigilance
Performance
Task Characteristics
Individual Characteristic
Environmental Characteristics
Vig
ilan
ce
Pe
rfo
rman
ce
Cognitive Science Laboratory, BHU
Vigilance Performance Measure
Existing approaches do not enable a directassessment of vigilance.
Available measures provide information about aspecific state of the operator like stress, fatiguemental workload etc. on the basis of :-
Behavioral performance.
Physiological Status.
Subjective Quarry.
Cognitive Science Laboratory, BHU
Performance Measure
Reaction Time: elapsed time between thepresentation of a sensory stimulusand the subsequent behavioralresponse.
Accuracy (Hit rates): number of correctdetection or response on giventask.
Cognitive Science Laboratory, BHU
Physiological Measure
Body Temperature:The degree of hotness or coldness of a body part.
Respiration: The number of breaths a person takes per minute.
Cognitive Science Laboratory, BHU
Vigilance Task Type
Sensory tasks, critical signals for detections atspecified changes in the physical attributes ofstimuli.
Cognitive task, the signals that involvesnumerical, linguistic or semantic discrimination.
ak XE w
Cognitive Science Laboratory, BHU
Ob
ject
ive The present study examined the
psychophysiological correlatesin terms of Body Temperatureand Respiration in cognitiveand sensory vigilance taskunder high task demand (highevent rate) condition.
Cognitive Science Laboratory, BHU
Sample & Design
Sixty students of the Banaras Hindu Universityparticipated in this study with mean age of 23.83± 2.87 years
Environmental Temperature: 30.78 ± 5.39 0C
Visual acuity : Normal (6/6) on Snellen.
A 2 (task: sensory and cognitive) × 4 (time period:four 10-min. blocks) mixed factorial design withrepeated measure on the last factor was used inthe present study.
Cognitive Science Laboratory, BHU
Task Properties & Schedule
Fixation
(500 ms)
Target or Non-target
(100 ms)
Reaction Time
(Max 1400ms)
Stimuli Visual & Black white background
Signal ratio 1: 4
Signal probability .20
Event rate 30 event /minute
Cognitive Science Laboratory, BHU
Cognitive Vigilance Task
•Press Space Bar when you found a Vowel in any place•Blank Screen is your Response time
Cognitive Science Laboratory, BHU
Sensory Vigilance Task
•Press Space Bar when you find a big Square•Blank Screen is your Response time
Cognitive Science Laboratory, BHU
Tools and Equipment
Insight 5133 (NASAN make) was used foronline recording of Respiration and Bodytemperature.
Super Lab (4.0) for display the task andperformance recording the ReactionTime.
SDT Analysis (developed by the same lab) forcalculating Sensitivity
Cognitive Science Laboratory, BHU
Lab Setting
Distance PC to
Eye= 12-18 inch
Experiment Cell (Height X width
X Length)= 9’ X 6’6” X 6’8”
Online
Recording
Participant
Cell
3 InchParticipant
Body Position
Electrode
placement
Body
Temperature
Sensor
Respiration
electrode
17 inch colour monitor
P-4 Processor and 512 MB RAM
Revolving Chair
Straight compact fluorescent light
Cognitive Science Laboratory, BHU
White wall
Procedure
Consent Form + Biographical
Questionnaire
Snellen Test (Eye Test)
Electrode Placement
Normal Recording
(10 min.)
Instruction + Demo
(3 min.)
Practice Session
(10 min.)
If Participant have 70% accuracy.
Main Session (40 min.)
Leave with thanks.
Cognitive Science Laboratory, BHU
Extraneous Variables
No difference found in both of the task
Age: CVT (23.67 2.48), SVT (24.0 3.24)
(t (58) = .657; p<.447)
Environmental Temperature
CVT (30.88 5.8), SVT (30.68 5.29)
(t (58) = .145; p<.885)
Weight CVT (62.9 10.13), SVT (60.3 8.36)
(t (58) = 1.08; p<.283)
Cognitive Science Laboratory, BHU
• Higher RT was found in CVTthan SVT.
ANOVA results revealed
• Significant main effects of
Block: (F (3, 174) =6.11;
p<.001, eta2=.095)
Task: (F (1, 58) =31.44;
p<.0001, eta2=.351)
• Interaction effects was alsofound significant (F (3, 174)
=5.36; p<.001, eta2=.085)
Result: Reaction time
250
300
350
400
450
500
RTB1 RTB2 RTB3 RTB4
Re
acti
on
Tim
e in
ms
cognitive Sensory
Cognitive Science Laboratory, BHU
• Higher accuracy was found inCVT than SVT.
ANOVA results revealed
• Significant main effects of
Block: (F (3, 174) =2.80;
p<.04, eta2=.046)
Task: (F (1, 58) =7.20;
p<.009, eta2=.110)
• Interaction effects was alsofound significant (F (3, 174)
=8.15; p<.0001, eta2=.123)
Result: Accuracy (Hit rates)
30
35
40
45
50
55
Hit B1 Hit B2 Hit B3 Hit B4
No
. of
Hit
s
Blocks – 10 min.
cognitive Sensory
Cognitive Science Laboratory, BHU
• Body Temperature wasfound higher in CVT thanSVT.
ANOVA results revealed
• Significant main effectsof
Block: (F (3, 174) =11.04;
p<.0001, eta2=.160)
Another effect was not
reached at significant level
Result: Body Temperature
35.25
35.35
35.45
35.55
35.65
35.75
35.85
Temp B1 Temp B2 Temp B3 Temp B4
Tem
pe
ratu
re in
0C
Block-10min.
cognitive Sensory
Cognitive Science Laboratory, BHU
Result: Respiration
13
14
15
16
17
18
19
Resp B1 Resp B2 Resp B3 Resp B4
Bre
ath
/m
in.
Block -10 min.
cognitive Sensory
• Body Temperature wasfound higher in CVT thanSVT.
ANOVA results revealed
• Significant main effectsof
Block: (F (3, 174) =11.21;
p<.0001, eta2=.162)
Another effect was not
reached at significant level
Cognitive Science Laboratory, BHU
Output
Sensory vigilance task is more demanding thancognitive vigilance task.
Respiration and Body Temperature decreases duringvigilance task.
There was not effect of vigilance ‘task type’ onrespiration and body temperature.
It can be concluded that respiration and bodytemperature are a sensitive measure but nothave a sufficient level of diagnosticity.
Cognitive Science Laboratory, BHU
Applications
Theoretical ApplicationThese findings may be used to develop a better taxonomyof vigilance task.
The real world applications of these findings includedomains in which monitoring plays a crucial part.
Basic research on attention can successfully be applied to anumber of human factors problems. Radar/Sonar monitoring Air-traffic control Prolonged driving Inspections Detections of criminals
Cognitive Science Laboratory, BHU
Thanks
for your Vigilance
Cognitive Science Laboratory, BHU