Demaree et al (2005)

Demaree, H.A., Everhart, D.E., Youngstrom,E.A., and Harrison, D.W. (2005)

Brain lateralisation of emotional processing: historical roots and a future incorporating 'dominance'.

Behav Cogn Neurosci Rev, 4, 3, 3-20

Quite a lot of information included from a psychiatric perspective, mostly ignored in this summary.

Historically 4 sequential theories, hemisphere specialisation, valence, approach/avoidance and dominance.  Ideas of emotional dominance should be explored further. Valence ideas mostly subsumed, by these authors at least, into an approach/avoidance model.

Hemisphere specialisation (and then) the Valence model

Right hemisphere specialisation for the perception of emotional expressions. Work based mainly on the study of emotions with negative valence eg sadness. (some more recent reports suggest that the left hemisphere is specialised for positive emotions and the right for negative emotions ie the valence theory. Furthermore a variant of this hypothesis contends that differential specialisation exists for the expression and the experience of emotion as a function of valence. Anterior regions of each hemisphere being specialised for the expression and experience of emotion (- or +) depending on valence whilst the posterior regions are specialised for perception of emotion

Most of the evidence  refers to either emotional facial expression or affective prosody.

Evidence from patients with right hemisphere lesions ( Adolphs, Damasio, Tranel &Damasio, 1996) eg aprosodia ( both sensory and motor) typically observed following right hemisphere lesions

Experimental evidence from participants who do not have hemisphere damage ie left visual field superiority for discriminating emotional faces

'consistent findings have been documented among patients undergoing intracarotid sodium Amytal procedures ...... Affective faces rated as less emotionally intense (compared to a base line) when shown to the anaesthetised right hemisphere, but not when shown to the anaesthetised left hemisphere

Electro physiological

'fMRI studies have found evidence of the specialisation of right hemisphere structures for the perception of emotion'

Left half of the face is more active than the right during emotional expression . The lower proportion of the face is predominately innervated by the contra lateral hemisphere...... suggesting right hemisphere control of facial expression (49 studies).

See bottom left paragraph of page 5 for the debate about the spontaneous versus posed neural pathways.

Experience of emotion (mood and affect)

Sodium Amytal, right carotid, indifferent, left carotid, catastrophic.

Patients with right hemisphere lesions tend to lack prosody

Experimental studies combined with electrophysiological monitoring

The approach- avoidance model

Overlap with the valence model is extensive ie most negative emotions leads to avoidance.  Therefore left for approach and right for avoidance

Lots of EEG evidence, (asymmetry between left and right) collected using all kinds of experimental paradigms.

Compared baseline frontal EEG activity to show that ' affective style (social initiation, positive affect versus isolated, onlooking behaviour) is correlated with the expected frontal asymmetry based on the location of approach/avoidance hemisphere specialisation

Anger studies - interesting because although a negative emotion it leads to approach type behaviours. Frontal asymmetries (left greater than right) recorded in children with impulsive disorders and also experimentally induced anger in adults)

Ideas about dominance

p12 ' the current authors believe that the approach-withdrawal model is compelling not only for its excellent fit to the available data but also it's theoretical importance (ie  to  species survival and procreation  ). At the same time, however, we believe that the designation of discrete emotions as 'approach' or 'withdrawal' is somewhat cumbersome. and the strengths of the motivational impulse can be quite difficult to quantify. In this last section, we make an argument for using 'dominance' as an important state construct underlying frontal asymmetry.

Circumflex model is relevant ' at least two dimensions are required to describe affective experience. Valence ( + or -  ) and arousal (low, high) most emotions can be distinguished from each other using this model. Many emotion researchers use the valence model to characterise emotional experience. (affective state). Authors, and others, argue for a third dimension, dominance, 'feeling of control and influence over everyday day situations. It would differentiate between fear and anger ( both high arousal with negative valence) but each with a distinct neural pathway.  This idea would fit with approach (emotional dominance) and avoid ( low emotional dominance - aka submission)

Hancock et al (2007)

Hancock, J.T., Landrigan, C., & Silver, C (2007)

Expressing Emotion in Text-based Communication

CHI 2007 Proceedings Emotion and Empathy. P 929-932

Theoretical Framework

SIP – strategic relational adaptation in mediated communication. (Parkinson relational alignment). P929 users employ the verbal cues present in CMC to convey relational information that may normally be tramsmitted via non-verbal cues

Method

This study influenced by Walther et al (2007) when confederate in a dyad asked express affinity ( or not)

Using IM Dyads ( undergraduates getting module accreditation) confederate asked to express emotion ( positive or negative) to naïve partner.

What strategies are used to express emotion? Confederate view. Confederates asked to respond to the questionnaire below

Positive and negative descriptives	P values
Punctuation 4.22 .45 2.95 .43	<0.05
Typed More 4.56 .40 3.95 .38 .	.28
Emoticons 4.00 .53 3.15 .50 .	.25
Explicit Emotion Statements 4.06 .41 3.00 .39 .	.07
Encourage Partner 3.28 .36 3.40 .34 .	.80
Respond Quickly 4.72 .37 3.20 .36	<0.01
Self-disclosure 4.50 .37 4.30 .36	.70
Agreement 5.00 .36 2.85 .34	<0.01

What is the textual evidence?

Linguistic analysis using LIWC

For the purposes of the study only the linguistic features shown in the following table were used ie relevant to the purpose of the study ( no further justification given!)

% measure – divides the frequency of the observed variable by the total number of words in the sample

	Linguistic Category positive then negative M SE M SE
Word Count	590.40 44.08 458.70 42.94 < .05	<0.05
Affect	4.44 .24 5.27 .33 < .05	<0.05
	Positive feeling .80 .12 .63 .11 .30	.30
	Negative feeling .11 .14 .55 .53 < .01	<0.01
	Emoticons .26 .09 .15 .07 .34	.34
Pronoun		.
	1st-Person 7.31 .38 6.72 .45 .33	.33
	3rd Person 1.38 .22 1.70 .28 .37	.37
Agrrement
	Negations 1.58 .15 2.29 .20 < .05	<0.05
	Assents 1.69 .20 2.51 .35 = .05	=0.05
ExclamationPoints	7.45 2.04 1.20 .69 < .05	<0.05
Msgs Per Minute	2.64 .22 2.37 .26 .43	.43

Note p931 ‘ Linguistic analysis of the texts revealed that several verbal dimensions differed significantly across the two emotion conditions although not necessarily in the manner the expressers reported in the questionnaire response

(KRO ? evidence for the involuntary)

Naives view

Naïves given questionnaire with 11 items to assess their ability to detect the expresser’s emotion.

FA gave 2 factors, perceived mood of expressor, and perceived relationship. Naïve partners were able to detect the expressor’s emotional state. Analysis suggest that negations and exclamation points were relied on most heavily by assessors when judging their partner’s affective state…

Discussion

Supports SIP .

Data suggests that four strategies ( ? use of this term) were used for differentiating between positive and negative emotions. Note that expressors reposnses to the questionnaires was not always born out by the linguistic analysis.

Walther et al agreement led to more liking.

• However for this data ( emotion) positive affect users disgreed significantly less.

• Negative used x5 times more negative affect terms, although they seemed to be unaware of this on the questionnaire ( KRO involuntary again)

• More x6 punctuation by positive expressors

• Positive reported responding quickly although analysis showed that they did not.