Chapter 1 Introduction to Social Neuroscience
Hyperscanning: simultaneous fMRI of two brains
Ecological validity: approach/measure meaningful outside the lab
Modularity: certain cognitive processes/brain regions are restricted in the type of information and
processing
- Phrenology: specialized routines and brain structures
Domain specificity: cognitive process is specialized for processing only one kind of information
Triune brain model: accumulated regions > more complex functions + control over ‘older’ layers
- Reptilian: action-reaction > approach/avoidance system
- Paleomammalian: emotionality, behavioural flexibility, attention, conditioning > limbic
system
- Primate/neomammalian: rationality, behavioural control, subjective/affective interaction >
neo-cortex
Reductionism: replacing one explanation by another more basic one
Reverse inference: infer nature of cognition from neuroscience
Blank slate: brain learns environmental contingencies without imposing any biases/constraints/pre-
existing knowledge
Chapter 2 The Methods of Social Neuroscience
Invasiveness: equipment internally or externally
Psychological methods
- Subjective measures
o Emotional experience (POMS)
o Personality questionnaires
o Use: control, correlation with other measure, compare studies
o External validity: extent to which a measure relates to something useful in real life
o But: acquiescence bias = tendency to respond affirmatively in surveys
- Observational measures
o Infancy, non-human species, participant can not know true nature of task
o Preferential looking: scoring amount of time looking at stimuli (eye tracking)
o Habituation: attention to repeated stimulus diminishes
o Inter-rater reliability: extent to which two independent observers generate the same
answers
o Blind scoring: observer is unaware of status of event
o Measuring the unconscious
Masking: junk visual material after visual stimulus
Stimulus outside locus of attention
- Performance measures
o Mental chronometry: study of time-course of information processing
o Speed-accuracy trade-off: forced to respond faster > less accurate
o IQ-test
o (emotion) recognition tests
o Selective attention
Implicit association task
(gaze) cueing task
Stroop task (interference of word/emotion/expression)
o But: hard to link directly to neural substrates and real-world behaviour
, Physiological methods
- Measure bodily reactions that underlie/precede behaviour
- Skin conductance response (SCR): small decrease in conductivity due to mild sweating (SNS)
- Heart rate, respiration: deceleration (prep), acceleration (fight/flight), heart rate variability
(HRV; more in PNS)
- Electromyography (EMG)
o Assessing electrical activity associated with muscle movement
o Facial expression: potential between electrodes > muscle activity
o Eyeblink startle response: motor response elicited by a loud unexpected sound;
modulated by emotional state
o Bodily responses usually unaware of stimulus/task
o But: not straightforward link to brain
Brain Imaging
- Electrophysiology
o Single-cell recording: recording action potentials of neurons per second
Rate coding + temporal coding (greater synchronization)
Direct related to neural activity
o Electroencephalography (EEG): records electrical signals through electrodes on scalp
Limited to cerebral cortex (synchrony + parallel activity) + poor spatial res
Frequency bands: delta (1-4Hz; motivational), beta (12-30Hz; cortex)
Event-related potentials (ERPs): averaged set of EEG recordings time-locked
to a particular event
Location, amplitude, timing of peaks > brain activity
- Magnetoencephalography (MEG): non-invasive recording of magnetic fields generated by
brain at scalp
o Not equally sensitive; expensive, limited
- Structural MRI: realignment of water molecules to magnetic field emits radio pulse
dependent on tissue properties
- Functional MRI (fMRI)
o Hemodynamic method: record blood flow/blood oxygenation
Oxygen (neural activity) slows realignment of water molecules
o BOLD response: change in blood oxygenation due to neural activity
Oxyhemoglobin > deoxyhemoglobin > distortions in local magnetic field >
decrease BOLD response
o Hemodynamic response function (HRF): change in BOLD response over time
Initial dip (oxygen consumption)
Compensation (increased blood flow)
Undershoot (venous relaxation > deoxyhemoglobin increase)
o But: temporal resolution in order of seconds
o Event-related design: all trials are randomly interspersed during stimulus
presentations but regrouped at analysis stage
o Block design: trials that belong together are grouped together during stimulus
presentation
o Pre-processing: stages between data collection and analysis
o Stereotactic normalization: mapping the voxels of an individual’s brain onto the
equivalent regions in a standard brain
o MNI template: ‘standard’ brain based on 305 brains
o Talairach coordinates: coordinate system of a ‘standard’ brain
o Smoothing: increasing the spatial extent of activity in voxels