basic bits of neuronal grammar friedemann pulvermüller mrc cognition and brain sciences unit...

Basic Bits of Neuronal Grammar

Friedemann Pulvermüller

MRC Cognition and Brain Sciences Unit Cambridge

Activity states:

• Ignition -- full activation, momentary

• Reverberation -- continuous enhanced activity following ignition

• Priming -- “parasitic” activity caused by strongly connected sets

• Rest -- inactivity

Activity states:

• Darker colours denote reduced activity states

The network:

The represented elements: WORDS

SEQUENCE FEATURES

The representing elements:WORD WEBS

The representing elements:WORD WEBS

SEQUENCE DETECTORS (SDs)

I

3 word inputcongruent with thenetwork structure

The sentence“Betty get up”

will appear in the inputand will not be accepted

by the network

Time step / Input / Process

0 -- All webs at rest

1 Betty Ignition of word web

2 -- Priming of SD

3 -- Priming of SD

4 -- Priming of word web

5 gets Primed ignition ofword web

6 -- Priming of SDsBackward ignition

7 -- Priming of SDsBackward ignition

8 -- Priming of word webBackward ignition

9 -- --

10 up Ignition of word web

11 -- Backward ignition

12 -- Backward ignition

13 -- Backward ignition

14 -- Backward ignition

15 -- Backward ignition

16 -- Backward ignition

17 -- Backward ignition

18 -- Deactivation

At time step 17, the 3 criteria for string acceptance were met:

• All activated word webs were visible (i.e., reverberated at the highest reverberation level).

• All activate word webs were satisfied (i.e., their set of sequence detectors reverberated at a high level).

• All active sets were synchronized (I.e., participated in a continuous wave of ignitions).

II

3 word inputincongruent with the

network structure

The sentence“Up get Betty”

will appear in the inputand will not be accepted

by the network

Time step / Input / Process

0 -- All webs at rest

1 up Ignition of word web

2 -- --

3 -- --

4 get Unprimed ignition I^of word web

5 -- Priming of SDThreshold regulation

6 -- Priming of SD

7 -- Priming of SD

8 Betty Unprimed ignition I^of word web

9 -- Priming of SDThreshold regulation

10 -- Priming of SD

11 -- Priming of SD

At time step 10, the 3 criteria for string acceptance were not met:

• Only 1 word web was visible (the 2 others were at lower activity levels, R2 and R3; cf. darker colours).

• No one of the 3 word webs was satisfied (SDs did not reverberate).

• No final synchronization process.

III

3 word input partly incongruent with the

network structure

The sentence“Up Betty get”

will appear in the inputand will not be accepted

by the network

Time step / Input / Process

0 -- All webs at rest

1 up Ignition of word web

2 -- --

3 -- --

4 Betty Unprimed ignition I^of word web

5 -- Priming of SDThreshold regulation

6 Betty Priming of SD

7 -- Priming of word web

8 get Primed ignition ofword web

9 -- Priming of SDBackward ignition

10 -- Priming of SDBackward ignition

11 -- Backward ignition

12 -- --

At time step 12, not all of the 3 string acceptance criteria were met:

• 2 out of the 3 activated word webs were visible (i.e., reverberated at the highest reverberation level).

• Only 1 out of 3 word webs were satisfied (i.e., their set of sequence detectors reverberated at a high level).

• Only 2 out of the 3 word webs were synchronized (I.e., participated in a continuous wave of ignitions).