Week 4 Flashcards
Libet’s experiment and wilful action
Wilful action usually involves an extended process of reflection, with feedback loops etc- This is not the case in this experiment
Can you predict behaviour better with fMRI and other neuroimaging methods than with psychological methods
NO
-Behaviour is hard to predict
-Many predictions are retrodictions
-AI developing algorithms to predict data- Threat to psychology
Prediction of behaviour (Bzdok & Ioannidis)
4 steps to predicting behaviour
1. Model building: Finding predictors for outcome- Choosing model that fits best- Significant correlation would mean somewhat accurate predictability
2. Internal validation: Test the model on data not used to build the model
3. External validation: Not done enough, Does the prediction work with external people
4. Generalisability and transposability- Exclusively WEIRD?
China using AI in primary schools
-3 electrodes sending real time data re brain waves to the teacher
-Details each students engagement levels at 10 minute intervals (Sent to parents)
-EEG v susceptible to artefacts
Bogus pipeline effect
-Common in forensic science
-Lie detection approach utilising a polygraph to measure variables in brain function/ skin conductance/ heart-rate/ breathing rate etc
-Usually doesnt detect lies but if someone is nervous
-People more likely to tell the truth
Cacioppo & Tassinary on Red
Paper about mind brain relationship
-Shows how in nearly all cases it is not a 1-1 relationship between psychological processes and physiological signs
fMRI experiment
Statistical models
-Univariate analysis: Compare experimental condition with data on a voxel-by-voxel (ROI) basis (Combining voxels to create ROIs improves signal: noise and multiple comparisons)
-Multivariate analysis: Correlating voxels with other voxels (Higher order correlation)- Not looking at one specific signal but looking at correlations/ relationships between signals
Searchlight strategy
-Take every voxel in the brain and compare them with each other
-Tried to predict when subjects were going to press left or right based on brain data prior to conscious awareness of the decision
-Based on data from 10s before decision (60% accurate)
-Brain areas associated with conscious control tasks were used
Neural correlates of sexual orientation
-Sexual content shown congruent or incongruent to their sexuality
-Subjective ratings of the images showed outliers and overlaps between groups
-Ventral striatum data matches pretty well to brain data
Interpretation of fMRI experiment
-Forward inference: During behavioural/ psychological task X engaging psychological process X, we found activation in brain area Y (Brain mapping)
-Reverse inference: During behavioural/ psychological test Z, we found activation in brain area Y, possibly engaging psychological process X (Dont know psychological process- Used for “mind reading”)- Dont know whether someone is lying or not, Need to infer from previous forward inferences
Conflict processing
-Associated with cingulate cortex and corpus callosum
-Idea that when people are lying, they are experiencing conflict which they have an intent of suppressing
Bayesian solution
Statistical equation showing probability of an inference
Delgado and brain chips
70s
Displayed in animals that he could control minds with the push of a button
Used electrodes on people who resisted previous treatments
Hess
Showed you can elicit behaviours by electrically stimulating different parts of the brain
Delgado and lobotomies
Thought lobotomies used by Moniz were too destructive and it was better to use electrical stimulation
Delgado and inducing emotions
Could induce emotions by stimulating different areas of the limbic system
-Triggering the septum could induce euphoria, counteracting depression and physical pain
Delgado taming a fighting bull
Caused a charging bull to stop a few feet before him by stimulating its caudate nucleus
Delgado and chimpanzees
-Programmed a stimoreceiver to detect spindles emitted by the amygdala
-When they were detected it produced an aversive reaction
-Within 6 days of this feedback the frequency of spindles dropped by 99%
-Calls this his most significant experiment
-Thought this could prevent disorders characterised by specific brain signals
Delgado and psychocivlized society
Claimed his technology was on the verge of creating a less cruel, happier and better man
Critics of Delgado
-Accused of trying to create a society where everyone who deviates from the norm will be surgically mutilated
-Also suggested brain stimulation is much less precise and beneficial than suggested
Delgado and non-invasive methods
Created a helmet that could deliver electromagnetic pulses to specific neural regions
-Success inducing drowsiness, alertness and treating tremors in Parkinsons patients
Brain implants today
-Cochlea implants most common today
-Clinical trials underway to stimulate vagus nerve to treat depression, OCD etc.
-Chips that stimulate optic nerve tested in blind subjects
-Electrodes that help with memory are a year or 2 away from testing in rats
(MI) Motor Imagery Data
Subject imagines the movement of a limb
What do BCIs do
Allow computers to be controlled by monitoring brain signal activity
-Imagining movements of a limb may be able to be used to control a BCI
