The recording of event related brain potentials (ERPs) and event related magnetic fields (ERFs)

The recording of event related brain potentials (ERPs) and event related magnetic fields

(ERFs)

axon

skull

pia mater

dura mater

The recording of event related brain potentials

active

relaxed

sleepy

sleep

deep sleep

coma

EEG Frequency BandsType Frequency (Hz) NormallyDelta up to 4 adults slow wave sleep

in babiesTheta 4 – 7 Hz young children

drowsiness or arousal in older children and adults

idlingAlpha 8 – 12 Hz relaxed/reflecting

closing the eyes

comaBeta 12 – 30 Hz alert/working

active, busy or anxious thinking, active concentration

Gamma 30 – 100 + certain cognitive or motor functions

EEG-activity

Auditory ERP

auditory stimulus

Onset Stimulus

Time (in milliseconds)

amplifier

signal averaging

Electrode configuration

Cognition related ERPs

Labelling conventions of ERP components and ERP effects

• Descriptive labelling:

P300, N400, N280, P1, N1

• Functional labelling:

Mismatch Negativity (MMN)

Error related negativity (ERN)

Syntactic Positive Shift (SPS)

Multidimensional nature of ERPs

• Polarity. N: negative goingP: positive going

• Latency. Exogenous componentsEndogenous components

• Amplitude

• Topographic distribution

Multidimensional nature of ERPs

Qualitatively different underlying processes show up in a qualitatively different way in the ERP waveform

(in contrast to RTs)

Discourse N400-effect

Sentence N400-effect

Van Berkum, Hagoort, & Brown, Journal of Cognitive Neuroscience, 1999

ERP effects vs components

An ERP effect is a modulation (mostly in amplitude) of a particular ERP component,

or just the difference between two conditions in the ERP waveform

N400 vs N400 effect

Brain activity for different word types250 ms

Content words Function words

+ 10 -10 V

ERPs vs. RTs

• Multidimensional nature of the signal

• Continuous nature of the signal

• No additional task requirements

Two definitions of ERP components

• A functional definition:

An ERP component is an aspect of the ERP waveform for which the polarity, latency, and topographic distribution are related to a specific cognitive process

Two definitions of ERP components

• A physiological definition

An ERP component is the scalp recorded activity of specific neural generators (or an ensemble of generators) in the brain.

Recording of ERPs and ERFs

Strength:

- high temporal resolution- direct measure of neural activity

Weakness:- measures only a part of the neural activity (open field)

- poor spatial resolution (inverse problem)

Hemodynamic method vs. ERP/ERF

- Neural activity does not have to be synchronous.

- Geometric orientation of the activated neurons is irrelevant.

- The amplitude of the signal is not only determined by the change in neural activity, but also by its duration.

- Changes in neural activity will only be picked up if these changes have a consequence for the net metabolic demand of the cells.

Neville et al. 1991

Neville et al. 1991

Hagoort et al. 2003, Fig. 1

Syntactic condition:Correct: De houthakker ontweek de ijdele schroef op dinsdag.(The lumberjack dodged the vain propeller on Tuesday.)Violation: De houthakker ontweek de ijdele schroeft op dinsdag.(The lumberjack dodged the vain propelled on Tuesday.)

Friederici et al. 1993, Fig. 1

Friederici et al. 1993, Fig. 2

Friederici et al. 1993, Fig. 3

Friederici et al. 1993, Fig. 4

Hahne & Friederici 2002, Fig. 1

(1) Correct Das Brot wurde gegessen.(The bread was eaten)(2) Semantically incorrect Der Vulkan wurde gegessen.(The volcano was eaten)(3) Syntactically incorrect Das Eis wurde im gegessen.(The ice cream was in-the eaten)(4) Semantically and syntactically incorrect Das Türschloß wurde im gegessen.(The door lock was in-the eaten)

Van den Brink & Hagoort 2004, Fig. 2

Fully congruent (phon +, sem +, syn +) Het vrouwtje veegde de vloer met een oude bezem gemaakt van twijgen(The woman swept the floor with an old broom made of twigs)Initially congruent (phon +, sem , syn ) Het vrouwtje veegde de vloer met een oude bedelde gemaakt van twijgen(The woman swept the floor with an old begged made of twigs)Fully incongruent (phon , sem , syn ) Het vrouwtje veegde de vloer met een oude kliederde gemaakt van twijgen(The woman swept the floor with an old messed made of twigs)

Hagoort 2003, Fig. 2

Korrekt

De kapotte paraplu staat in de garage.

Semantische Verletzung

De eerlijke paraplu staat in de garage.

Syntaktische Verletzung (Genuskongruenz)

Het kapotte paraplu staat in de garage.

Semantische und syntaktische Verletzung

Het eerlijke paraplu staat in de garage.

Dercommon/neuter kaputte/ehrliche Schirm steht in der Garage.

Art der Verletzung ERP-Effekt

1. semantisch N400

2. syntaktischa) Phrasenstruktur-Verletzung/ Wortkategorie-Verletzung

ELAN (early left anterior negativity)P600(N400) -> eher anteriore Negativität

a1) unerwartete Phrasen P600zentrale-posteriore Negativität (400ms)

b) Kongruenz zentrale-okzipitale Negativität (300- 400ms)

b1) S-V-Kongruenz NUM P600zentrale-okzipitale Negativität (300- 400ms)

b2) DET-N-Kongruenz GEN P600(N400 boost)

Friederici & Frisch 2000

*Anna weiß, dass der Kommissar (NOM) denBanker (ACC) abbeizte (V) und wegging.

Anna weiß, dass der Kommissar (NOM) denBanker (ACC) abhörte (V) und wegging.

Friederici & Frisch 2000

*Anna weiß, dass der Kommissar (NOM) denBanker (ACC) abreiste (V) und wegging.

Anna weiß, dass der Kommissar (NOM) denBanker (ACC) abhörte (V) und wegging.

Osterhout et al. 1994

The judge …

Osterhout et al. 1994

For breakfast the boys would eat toast and jam.

For breakfast the boys would plant flowers in the garden.

N400 effect, small P600 effect

For breakfast the boys would eat toast and jam.

For breakfast the eggs would eat toast and jam.

P600 effect, no N400 effect

Kuperberg et al. (2007)

For breakfast the boys would eat toast and jam.

For breakfast the eggs would plant flowers in the garden.

P600 effect, no N400 effect

The meal was devouring. (Kim and Osterhout, 2005)P600, no N400The dusty tabletops were devouring thoroughly.N400, no P600Control: The hearty meal was devoured..

The javelin has thrown the athletes. (Hoeks et al., 2004; Dutch)P600, no N400

The cat that from the mice fled ran across the room. (Kolk et al. 2003; Dutch)P600, no N400

Zuweisung grammatischer/thematischer Rollen vor dem Verb

Schlesewsky & Bornkessel (2006), Fig. 2

dass Richard Künstlerinnen gesehen hat,

dass Richard Künstlerinnen gesehen haben

dass Richard Künstlerinnen gedankt hat

dass Richard Künstlerinnen gedankt haben

Unterschied zwischen Reanalyse

Subjekt/Agens > direktes Objekt/Thema (P600)

und

Subjekt/Agens > indirektes Objekt/Rezipient (N400)

Schlesewsky & Bornkessel (2006), Fig. 4

Vielleicht gefällt Richard dem Regisseur…

Vielleicht gefällt Richard der Regisseur…

Vielleicht droht Richard dem Regisseur…

Vielleicht droht Richard der Regisseur…

Unterschied zwischen Reanalyse

Subjekt/Agens > indirektes Objekt/Rezipient (N400, P600)

und

Subjekt/Thema > indirektes Objekt/Experiencer (N400)

Bornkessel et al. (2002), Fig. 1

unambiguous(1)…dass der Professor

dem Gärtner dankt/gefällt

that [the professor]-a NOMINATIVE[the

gardener]- DATIVE thanks/pleases

that the Professor thanks/is pleasing to the

gardener

> Reanalyse

Subjekt/Agens > Subject/Experiencer

Änderung der thematischen aber nicht der grammatischen Rolle

ruft frühe Positivität hervor

Bornkessel et al. (2002), Fig. 2

ambiguous

(2)..dass Maria Sängerinnen dankt/gefällt

that Maria-AMB singers-AMB thanks/pleases

that Maria thanks/is pleasing to singers

>

Der Effekt tritt nicht auf, wenn die NPs keinen Hinweis auf thematische/grammatische

Rollen geben