Are Faces Special? P2: Neuroscience

Question 1

What is an fMRI?

Answer 1

Non invasive imaging technique that detects brain activity by detecting changes in oxygen levels in the blood
- Relies on cerebral blood flow and neuronal activation being coupled

Question 2

What are the advantages and limitations of fMRI?

Answer 2

+ve
- Readily available in clinical and academical research
- Non-invasive
- Provides high resolution anatomic scans

-ve
- Poor temporal resolution

Question 3

What was part 1 of Kanwisher’s experiment (1997) ?

Answer 3

• 20 healthy subjects <40
• Authors searched fot any occipitotemporal areas that may be specialised for face perception by looking within each subject region in the ventral pathway that responded more significantly during passive viewing of faces

Question 4

What did the results of P1 of Kanwisher’s study show?

Answer 4

Only the fusiform gyrus was activiated consistently across subjects for alll the faces

Question 5

What was the comparison between in part II of Kanwisher’s study?

Answer 5

Intact faces and scrambled faces in which the black regions were rearranged to create a stimulus unrecognisable as a face

Question 6

What did the data in P2 in K’s study show?

Answer 6

Higher activation for face than non face stimuli

Question 7

What was the summary of P2 of K’s study?

Answer 7

The region in each subject’s fusiform gyrus that responds more strongly to faces than objects also responds more strongly to intact than scrambled faces and to faces than houses

Question 8

What was Part III of K’s study?

Answer 8

• Subjects viewed images of people who were wearing a black hat vs human hands

Question 9

What was P3 of K’s meant to test?

Answer 9

• Would the response of the candidate face area generalise to the different viewpoints?
• Is the area involved in recognising the face on the basis of the hair and other external features on the head or on the basis of its internal features?

Question 10

What did P3 of K’s study find?

Answer 10

Higher activation for faces vs hands.

Question 11

What is the face fusiform area (FFA)?

Answer 11

Cortical region in the fusiform gyrus that is found to be more highly activated when P’s are presented with faces than when they viewed sets of non-face stimuli

Question 12

What was Gauthier et al (1999) study?

Answer 12

• Subjects trained with Greebles until they were as fast at categrosiing them at indi. level as they were at family level

Question 13

What was expertise training in terms of greebles?

Answer 13

• Ps trained to categorise 30 Greebles at ‘family’ and ‘individual’ level until they could make both types of judgements
• Performance assessed in name-verification trials

Question 14

What tasks were part /of Gauthier’s experiment

Answer 14

• 8 sequential matching tuns per fMRI session, 4 with Greebles and 4 with faces
• 5 stimulus sets, each including 8 grayscale faces and 8 greebles of the same family were used in sequential matching tasks
• Pictures repeated 12x per session

Question 15

What were the results of Gauthier’s study?

Answer 15

• Confirmed intial preference for faces, more upright-specific activation found for faces over Greebles was stronger in R Hemisphere

Question 16

What implications did the results of Gauthier’s study have?

Answer 16

Interpreting the role of th fusiform ‘face area’ in visual object recognition
- The inversion effect can be obtained for faces in face-specific area, and a similar effecr can be produced for novel objects after expertise training

Question 17

What is electroencephlography (EEG) ?

Answer 17

• Measures electrical activity generated by the synchronised activity of thousands of neutrons - allows detection of activity in cortical areas

Question 18

What are Event related potentials?

Answer 18

• Small voltages generated in the brain structures in response to specific stimuli

Question 19

How are ERP’s obtained?

Answer 19

Averaging EEG fragments in multiple trials - non-invasive

Question 20

What is the N170?

Answer 20

Extensively studied ERP marker of facial processing

Question 21

What did Rosin et al (2002) find about the N170?

Answer 21

ERPs recorded before the training phase revealed a a larger inversion effect on the N170 component for faces compared to that found for Greebles

Question 22

Who did the Checkerboard Inversion Effect on the N170 experiment?

Answer 22

Civile, Zhao et al (2014)

Question 23

What were participants instructed to do during the categorization phase? (C&V)

Answer 23

Press a key to start, then categorize checkerboard stimuli into two categories using “x” or “.” with immediate feedback on accuracy.

Question 24

How many checkerboard exemplars were used in the categorization phase, and how were they distributed?

Answer 24

128 exemplars total: 64 from each of two categories (e.g., A & C).

Question 25

What were participants encouraged to do before categorizing each checkerboard and what happened if a participant did not respond within 4000 milliseconds during the categorization phase?

Answer 25

Scan the whole checkerboard thoroughly and they were timed out

Question 26

What was the purpose of the study phase in C&V's experiment, and how was it structured?

Answer 26

To study 64 exemplars: 32 from a familiar category (e.g., A) and 32 from a novel category (e.g., B), shown one at a time for 3000 ms.

Question 27

How were the study phase exemplars oriented in C&V?

Answer 27

16 upright and 16 inverted in both familiar and novel categories.

Question 28

What did the recognition (old/new) task involve in C&V?

Answer 28

Identifying whether 128 exemplars (64 old, 64 new) had been seen in the study phase using keyboard responses.

Question 29

What did Galen discover?

Answer 29

Able to alleviate pain using alive sting rays - they produced electircal current

Question 30

Who created the first electric battery?

Answer 30

Alessandro Volta

Question 31

What did Aldini do?

Answer 31

Completed the first study in which he sued the early form of tDCS to imprive the moods of subjects suffering from melancholia

Question 32

What is tDCS?

Answer 32

Transcranial Direct Current Stimulation

Question 33

What replaced tDCS and what is it?

Answer 33

ECT - electroculvulsive therapy

Question 34

How does current tDCS work?

Answer 34

Target channel electrode and reference channel elctrode both placed on scalp delivering continuous low stimulation

Question 35

What is neurostimulation?

Answer 35

A new line of research based on using a particular tDSC procedure that has provided evidence for thr inversion effects for checkerborads and faces