The Physiology and Chemistry of the Brain

Change Across the Night

The Physiology and Chemistry of the Brain

Change Across the Night

A Good Night’s SleepA Good Night’s Sleep

11 PM 1 AM 3 AM 5 AM 7 AM

Wake

I/REM

II

III

IV

Sleep onsetSleep onset

Stage 2 NREMStage 2 NREM

SWSSWS

REM sleepREM sleep

Sleep PhysiologySleep PhysiologyEEG

Wake

Stage 2

Stage 4

REM2 sec

EOGStage 1

Stage 2

REM

EMGWake

Stage 4

REM

Neuromodulation Varies Across the Wake-Sleep Cycle

Neuromodulation Varies Across the Wake-Sleep Cycle

Active Wake

ACh

NE5-HT

Quiet Wake SWS REM

Ach: acetylcholineNE: norepinephrine (noradrenalin)5HT: serotonin

Regional Activation in REM SleepRegional Activation in REM Sleep

Hippocampal-Neocortical DialogHippocampal-Neocortical Dialog

Hippocampus

Neocortex

Sleep Enhances Memory

Sleep Enhances Memory

Sleep Consolidates Perceptual LearningSleep Consolidates

Perceptual Learning

• Vipul Patel• Beth Schirmer• Dana Whidbee• LaTanya James

0

10

20

6 12 18 24

Test interval (h)

Imp

rove

men

t (m

s)Daytime

Overnight

**

*

Time Course of ImprovementTime Course of Improvement

0

5

10

15

20

25

30

0 1 2 3 4 7

Days

Imp

rovem

ent

(ms)

Total sleep time (h)

-20

0

20

40

6 7 8 9 10 11

r = 0.62p = 0.006

11 PM 1 AM 3 AM 5 AM 7 AM

Wake

I/REM

II

III

IVSWSSWS

REM sleepREM sleep

Learning Across the NightLearning Across the Night

Quartile

Pea

rso

n r

-val

ue

-0.2

0.0

0.2

0.4

0.6

0.8

1 2 3 4

SWS

p = 0.05

p = 0.01

REM

Training

SWS1

REM REM 44v = SWS1 x REM4

Improvement Correlates with Early SWS and Late REM

Improvement Correlates with Early SWS and Late REM

r2 = 0.79 p < 0.0001

0

10

20

30

40

50 100 150 200

Imp

rov

eme

nt

(ms

)

SWS1 x REM4

“24/7” Burn Out!!“24/7” Burn Out!!

• Dan Luskin• Sara Mednick• Neha Pathak

Overtraining on TDT

Naps, SWS, & REMNaps, SWS, & REM

-15

-10

-5

0

5

10

15

Improvement (ms)

(n=28)

(n=17)

+SWS+REM

(n=13)

+SWS

(n=13) (n=2)

no nap

60’ nap

90’nap

11 PM 1 AM 3 AM 5 AM 7 AM

Wake

I/REM

II

III

IVSWSSWS

REM sleepREM sleep

Training

SWSStabilize

REM REM

Enhance

Sleep Consolidates Motor Learning

Sleep Consolidates Motor Learning

• Matthew Walker• Tiffany Brakefield• Alexandra Morgan

1 2 3 4

Sequence4-1-3-2-4

Learning Rate Saturates RapidlyLearning Rate Saturates Rapidly

10 PM

10 AM

1

12

Post-training

# S

eq

uen

ces /

30 s

ec

Baseline Training Trials(lasting 12 mins)

2 3 4 5 6 7 8 9 10 11 12

16

20

24

Sleep Enhances PerformanceSleep Enhances Performance

10PM10AM20

22

24

26

28

10AM

SLEEP

p<0.0001

# S

eq

uen

ces /

30

sec

10PM20

22

24

26

28

10PM10AM

p<0.0001

SLEEP

A Good Night’s SleepA Good Night’s Sleep

11 PM 1 AM 3 AM 5 AM 7 AM

Wake

I/REM

II

III

IV Stage 2 NREMStage 2 NREM

25

% Overnight improvement

% Stage 2 NREM sleep – 4th Quarter

r =0.72 p=0.008

45 65 85

10

20

30

40

0

Overnight improvement and Late Stage II Sleep

Overnight improvement and Late Stage II Sleep

Who’s Getting Better?Who’s Getting Better?

Not SchizophrenicsNot Schizophrenics

1

12

10 PM

Post-training

# S

eq

uen

ces /

30 s

ec

Baseline Training Trials(lasting 12 mins)

2 3 4 5 6 7 8 9 10 11 12

10 AM

Retest Next day

16

20

24

28

Next day

Sz. next day

4

5

6

7

8

9

10

11

12

13

Schizo.

Sch

izop

hre

nic

s (s

eq

/30s)

Not SchizophrenicsNot Schizophrenics

Where Are They Getting Better?

Where Are They Getting Better?

R motor cortex hippocampus medial prefrontalL cerebellum(precision) (movement sequencing)(mapping of intent)

Limbic systemParietal cortex(emotional task burden)(consc spatial monitoring)

How Are They Getting Better?How Are They Getting Better?

Sleep Enhances PerformanceSleep Enhances Performance#

Seq

uen

ces /

30

sec

10AM 10PM20

22

24

26

28

10AM

SLEEP

p<0.0001

10PM20

22

24

26

28

10PM10AM

p<0.0001

SLEEP

Sleep Enhances Where NeededSleep Enhances Where Needed

200

400

600

Sequence Transition

Reacti

on

tim

e (

ms)

4 1 3 2 4

125

175

200

Sequence Transition

150

4 1 3 2 4

25

15

5

-5

Perc

en

t Im

pro

vem

en

t

Un

i -

5

Bi -

5

Un

i -

9

Bi -

9

Sleep Enhances Where NeededSleep Enhances Where NeededFastest Transitions

Un

i -

5

Bi -

5

Un

i -

9

Bi -

9

Slowest Transitions

How Smart is Sleep?How Smart is Sleep?

• Carlyle Smith• Jan Born

Complex Problem SolvingComplex Problem Solving

Control group

0

20

40

60

80

100

d 1

Mov

es

0

20

40

60

80

100

Presleep EtOHd 1

Mov

esd 8 d 8

WAKE/NIGHT

WAKE/DAY

ZZZ ...

Development of InsightDevelopment of InsightWagner et al. (2004) Nature 427: 352

11 11 44 44 99 44 99 44

11 99 11 44 44 11 9999

20%

40%

60%

Su

bje

cts

gain

ing

insi

ght

0%

Associative Memory is Altered During Sleep

Associative Memory is Altered During Sleep

• Cindi Rittenhouse• Jen Holmes• Beth Schirmer• Lauri Scott

Semantic Priming

(580 ms)thief wrong

(560 ms)right wrong

paper wrong (600 ms)

0.01 0.17 0.01

Weak

Strong

msec

0

10

20

30

REMNREM PM

New Experiences are Replayed at Sleep OnsetHypnagogic dreams

New Experiences are Replayed at Sleep OnsetHypnagogic dreams

• April Malia• Denise Maguire• David Roddenberry• Karen Emberger• Laura Babkes

Hypnagogic Images of TetrisHypnagogic Images of TetrisHypnagogic Images of TetrisHypnagogic Images of Tetris

Group (n) Nights % Ss % Rpts

Novices 2 75% 10.4%

Experts 2 or 3 50% 4.7%

Reports of Tetris ImageryReports of Tetris Imagery

“Just seeing Tetris shapes floating around in my head like they could in the game, falling down, sort of putting them together in my mind” (JEG - Day 2)

NOVICE

“…seeing in my mind how the game pieces kind of float down and fit into the other pieces and am also rotating them” (TRP - Day 2)

EXPERT

ASSOCIATED IMAGERYASSOCIATED IMAGERY

““I see just a little part of the game for a I see just a little part of the game for a second. It’s weird also, because I don’t see second. It’s weird also, because I don’t see it the way we play it on this computer. I it the way we play it on this computer. I see it like I used to play it at home, where see it like I used to play it at home, where it’s in different colors and stuff like that. it’s in different colors and stuff like that. And the boxes look a little different.” (EH)And the boxes look a little different.” (EH)

Amnesiacs 3 60% 7.4%

Hypnagogic Images of TetrisHypnagogic Images of TetrisHypnagogic Images of TetrisHypnagogic Images of Tetris

Group (n) Nights % Ss % Rpts

Novices 2 75% 10.4%

Experts 2 or 3 50% 4.7%

Reports of Tetris ImageryReports of Tetris Imagery

“Just seeing Tetris shapes floating around in my head like they could in the game, falling down, sort of putting them together in my mind” (JEG - Day 2)

NOVICE

“…seeing in my mind how the game pieces kind of float down and fit into the other pieces and am also rotating them” (TRP - Day 2)

EXPERT

“I see images that are turned on their side. I don’t know what they are from, I wish I could remember, but they’re like blocks” (JEG - Day 2)

AMNESIAC

Learning Experiences are Replayed at Sleep Onset

(Improved)

Learning Experiences are Replayed at Sleep Onset

(Improved)

• Karen Emberger• Laura Babkes

Alpine Racer II

QuickTime™ and aSorenson Video decompressorare needed to see this picture.

Alpine Racer IIAlpine Racer II

42% of first night reports contain skiing 42% of first night reports contain skiing imageryimagery

3 out of 3 controls who only watched3 out of 3 controls who only watched

Kinesthetic imageryKinesthetic imagery 11 players (69%)11 players (69%) 1 control (33%)1 control (33%)

Skiing imagerySkiing imagery 14 out of 16 players (88%)14 out of 16 players (88%)

Alpine Racer ImagesAlpine Racer Images

““I keep seeing all the places where I fall- like, hit the walls. It’s kind of annoying; and then my legs fly up in the air.” (SEC)

“I can sort of feel the motions of the game but more not really seeing it.” (MLC)

“I envisioned myself skiing, and for a second there it felt like I was skiing backwards - something I used to attempt when I was younger.” (CMD)

Delayed Onset ReportingDelayed Onset Reporting

}REPORTS

Standard protocol0 2 3 4 5 6 7 81

}Math problems

REPORTS

Delayed onset0 2 3 4 5 6 7 81

Delayed Onset ReportsDelayed Onset Reports

"I felt like I was sort of sliding downhill again. And, um ... there were instructions and a person and uh, I don't know." (JAV, rpt 6)

"I was having a rather vivid image as though I was moving forward through some kind of a forest... I was moving forward very stiffly. Um, my entire upper body was incredibly straight ... it felt almost as if I was moving forward on a conveyor belt, and, without my legs actually moving." (MAM, rpt 8)

"I felt as though I was falling downhill. And I was dreaming about like instructions to a young king or something." (JAV, rpt 4)

Sleep, Memory & DreamsSleep, Memory & Dreams

√ The physiology and chemistry of the brain change across the night

√ Sleep consolidates and enhances memory√ Sleep alters associative memory processes√ Sleep finds patterns in our daily experiences,

even when we don’t know that they exist √ And dreams are part of the story