This presentation discusses in detail the evolution of the EEG patterns in the human brain, as the brain develops and matures. The sequence of changes as well as the shifting patterns coinciding with Myelination are discussed.
7. Full Term (36-41 week),
contd…
Spindles
Vertex waves and K complexes
None (but scanty ripples)
None
Positive occipital sharp transients of sleep
None
Slow and fast activity in sleep
Much delta and theta activity, continuous
in REM sleep
REM sleep
Continuous slow activity, REM in EOG
(more REM or “active†than non-REM
sleep)
Rhythmical frontal theta activity
(6–7/sec)
14 and 6/sec positive spikes
Psychomotor variant (marginal
abnormality)
Sharp waves, spikes
None
None
None
Some minor sharp transients (normal)
(abnormal spikes more consistent and
prominent)
8. Infancy (2-12 months)
Continuity
Interhemispheric synchrony
Differentiation of waking and sleeping
Continuous
No significant asynchrony
Good
Posterior basic (alpha) rhythm
Starting at age 3–4 mos at 4/sec, reaching
about 6/sec at 12 mos
Slow activity (awake)
Temporal theta
Occipital theta
Fast activity (awake)
Low voltage
Considerable
None
None
Very moderate
Uncommon, usually abnormal
Hyperventilation
Intermittent photic stimulation
Not feasible
Improving driving to low flash rates after age 6
mos
Around age 6 mos, appearance of rhythmical
theta
Drowsiness
15. Early Childhood (12 to 36
months) contd…
Spindles
In 2nd yr, sharp and shifting, then
symmetrical with vertex maximum
Vertex waves and K complexes
Large, becoming more pointed
Positive occipital sharp transients of sleep
Poorly defined
Slow and fast activity in sleep
Marked posterior maximum of slow
activity; often a good deal of fast activity
REM sleep
Mostly slow, starting to become more
desynchronized
Rhythmical frontal theta activity
(6–7/sec)
14 and 6/sec positive spikes
Psychomotor variant (marginal
abnormality)
Sharp waves, spikes
Seldom in 3rd yr of life
Rare
None
Spikes in seizure-free children, mainly
occipital (mild abnormalities)
19. Pre School Age (3 to 5 yrs),
contd…
Spindles
Vertex waves and K complexes
Typical vertex maximum
Large with an increasingly impressive
sharp component
Positive occipital sharp transients of
sleep
Slow and fast activity in sleep
Poorly defined
Predominant slowing but less prominent
posterior maximum
REM sleep
Slow activity with some desynchronization
Rhythmical frontal theta activity
(6–7/sec)
14 and 6/sec positive spikes
Psychomotor variant (marginal
abnormality)
Sharp waves, spikes
May occur, not very common
May occur, not very common
Probably none
Spikes in seizure-free children, mainly
occipital, also Rolandic (slight
abnormalities)
21. Older Children (6-12 years)
contd…
Spindles
Vertex waves and K complexes
Typical vertex maximum
Large with a prominent sharp component
Positive occipital sharp transients of
sleep
Slow and fast activity in sleep
Still poorly defined but gradually evolving
REM sleep
Rhythmical frontal theta activity
(6–7/sec)
14 and 6/sec positive spikes
Psychomotor variant (marginal
abnormality)
Sharp waves, spikes
Much diffuse slowing, slightly decreasing
voltage
Less slowing and increasing
desynchronization
A bit more common
Fairly common
Uncommon
Spikes in seizure-free children, mainly
Rolandic (central-mid-temporal), slight to
moderate abnormalities; physiological
occipital spikes in congenitally blind
children
24. Adolescents, contd…
Spindles
Vertex waves and K complexes
Typical vertex maximum
Not quite as large, sharp component not
quite as prominent
Positive occipital sharp transients of sleep
Often very well developed
Slow and fast activity in sleep
Much diffuse slowing with further
attenuation of voltage
REM sleep
Rhythmical frontal theta activity
(6–7/sec)
14 and 6/sec positive spikes
Psychomotor variant (marginal
abnormality)
Sharp waves, spikes
Mature desynchronization
A bit more common, declining at end of
period
Fairly common
More common (although relatively rare)
Benign Rolandic spikes usually disappear
before beginning of this period