Effect of physical activity
on cognitive functions:
molecular-genetic and brain
mechanisms
Tonevitsky A.G., Smirnov K.S.
Moscow State University,
Department Of Psychology
Main Topics
• How does physical activity affect on
cognitive functions?
• What molecular-genetic and brain
mechanisms underlie these changes?
Time Perception
• Internal representation of temporal durations
• Reflects cyclic nature of external and internal
processes
• Associated with physiological parameters such as
heart and respiratory rate etc.
• Connects with psychological and social
characteristics (types of CNS; temperament;
impulsivity; ethnical background)
• Dopamine and serotonin systems are reported to
be connected with time perception
Molecular genetic model
of 5HT activity
MAOA (5-HT degradation)
MAOA VNTR
5-HTT (re-uptake of the 5HT)
5-HTTLPR
5-HT2a receptor
5-HT2a T102C
Higher 5-HT activity = less (MAOA and 5-HTT) and more 5-HT2a receptor
Molecular genetic model
of DA activity
COMT (DA degradation)
COMT V158M
DAT (re-uptake of the DAT)
DAT VNTR
DRD2 receptor
DRD2 TaqI A
Higher DA activity = less (COMT and DAT) and more DRD2 receptor
Findings on genetic basic of time
perception
• Carriers of genotypes related to the increased
level of 5-HT transmission are characterized more
pronounced “subjective shortening” of elapsed
time intervals and less accurate orienting in time
• Carriers of less active variant of COMT tend to
overestimate short (1-2 sec) durations in duration
reproduction task and underestimate long
durations in orienting in time
Methods
•
•
•
•
•
•
•
Subjective second
Maximal tapping
Comfort tapping
Attention Network Test
EEG
Heart rate
Scaled self-report (health, mood, activity)
Participants
• Elite athletes:
o Olympic biathlon team (11 males, 4 females)
o Olympic cross skiing team (19 males, 10
females)
• Nonprofessional athletes:
o University wrestling team (15 males)
• Controls:
o healthy students not involved in regular sport
activity (15 males, 10 females)
Results
subjective second
1600
1400
1200
subjective second
variability (std)
*
*
*
300
250
*
1000
200
800
BL
600
AP
BL
150
AP
100
400
200
50
0
0
Wrestlers Biathletes
Wrestlers
Biathletes
maximal taping
250
self report (wrestlers)
*
5.6
*
5.4
200
5.2
150
100
BL
5
AP
4.8
BL
AP
4.6
50
4.4
0
Wrestlers Biathletes
4.2
Health
Activity
Mood
Conclusions
•Significant decrease of subjective second and
maximal tapping time after physical load
• Significant difference between elite and
intermediate level athletes
• Increase level of activity
Attention
According to the theory of attention
networks, there are three basic systems:
• alerting or vigilance system
• orienting system or system of selectivity
• executive or conflict system
Executive attention - anterior cingulate and prefrontal cortex - dopamine
Alerting attention - subcortical brain structures - norepinephrine
Orienting attention - structures of the visual cortex - acetylcholine
Attention Network Test
designed to investigate all three systems by combining different types
of cueing and target stimuli
No alerting effect of cue for elite
biathletes
alerting attention f or congruent stimulus
Current ef f ect: F(2, 61)=3,4165
p=,03923
70
60
50
ms
40
30
20
10
0
biathlon
ski
control
Smaller orienting effect of cue for elite
biathletes
oriention attention f or congruent stimulus
Current ef f ect: F(2, 61)=6,4247
p=,00294
120
110
100
90
80
ms
70
60
50
40
30
20
10
0
biathlon
ski
control
Though biathletes scores for orienting are smallest they
achieve relatively biggest profit for incongruent stimuli
Wilks lambda=,82197, F(4, 120)=3,0898
p=,01842
120
110
100
90
80
70
60
50
40
30
biathlon
ski
sport
control
conguent
incongruent
Contingent negative variation (CNV)
for no cue condition
response
N1 component, latency effect
Elite athletes
central cue
no cue
*
Controls
central cue
no cue
Topography of ERP to the target
N1 (200 ms post-target)
Controls
Alerting
=
no cue
+
center cue
Elite
athletes
Conclusions
• Elite athletes has lower alerting and orienting
scores
• Low alerting and orienting scores in elite
athletes is due to increased “readiness” in the
no cue condition, revealed by higher CNV
• Elite athletes has higher and earlier N1
component even in no cue condition
• Demands of sport discipline also effect on
efficiency of alerting system
Thanks to
• Sysoeva Olga
• Polikanova Irina