Moqian

Back to Psych 204 Projects 2009

Methods

Stimuli

There are six dynamic stimuli categories: emotional faces, communicative faces, emotional bodies, hand gestures, scenes and vehicles. all of the stimuli are shown in 2s movie clips.
Emotional faces are faces with 6 different emotions: disgust, happiness, anger, fear, sadness and surprise.
Communicate faces are faces nodding, shaking, talking without sounds etc. Actors are both adults and kids.
Hand gestures are hands that thumb up, thumb down, punch, point or clap.
Emotional bodies are all back of the body, without face appeared in the video. Emotions include anger, sadness, happiness and fear. All actors are adults.
All the stimuli are self-moving, with the camera staying still.
In each category block, the identities and movement types are different. Identities could be the same across blocks.

Design

This is a blocked-design experiment. All of the stimulus categories were shown in a block. There are 6 video clips from the same stimulus category in each block, each lasts 2s, thus make a block of 12s.
Each scan consists of 21 blocks (4 faces, 4 bodies, 4 vehicles, 4 scenes, 5 blanks).
Subjects perform an one-back task by pressing a button when two successive images are the same.
Subjects can freely view the videos during the movie blocks, and need to fixate in the blank blocks.

Subjects

Subjects are 4 adults and 4 kids. Written consent was obtained from each subject, and the procedures were approved by the Stanford Internal Review Board on Human Subject Research.

MR acquisition

We collected 32 slices at a resolution of 3.125*3.125*3mm using a two-shot T2* spiral acquisition sequence (Glover, 1999). Fov =200mm, TE= 30ms, flip angel=76degree, Bandwidth = 125 kHz, TR=2000ms. Inplane anatomicals were acquired with the same prescription using a two-dimensional SPGR sequence.
Scan plane was oblique to cover the occipitotemporal cortex.

MR Analysis

The MR data was analyzed using mrVista software tools.

Pre-processing

All data were slice-time corrected, motion corrected, and repeated scans were averaged together to create a single average scan for each subject. Et cetera.

Results - What you found

Retinotopic models in native space

Some text. Some analysis. Some figures.

Retinotopic models in individual subjects transformed into MNI space

Some text. Some analysis. Some figures.

Retinotopic models in group-averaged data on the MNI template brain

Some text. Some analysis. Some figures. Maybe some equations.

Equations

If you want to use equations, you can use the same formats that are use on wikipedia.
See wikimedia help on formulas for help.
This example of equation use is copied and pasted from wikipedia's article on the DFT.

The sequence of N complex numbers x₀, ..., x_N−1 is transformed into the sequence of N complex numbers X₀, ..., X_N−1 by the DFT according to the formula:

$X_k=\sum _{n=0}^{N-1}{x}_n{e}^{-\frac{2\pi i}{N}kn}k=0,\dots ,N-1$

where i is the imaginary unit and $e^{\frac{2\pi i}{N}}$ is a primitive N'th root of unity. (This expression can also be written in terms of a DFT matrix; when scaled appropriately it becomes a unitary matrix and the X_k can thus be viewed as coefficients of x in an orthonormal basis.)

The transform is sometimes denoted by the symbol $ℱ$, as in $𝐗=ℱ\left\{𝐱\right\}$ or $ℱ\left(𝐱\right)$ or $ℱ𝐱$.

The inverse discrete Fourier transform (IDFT) is given by

$x_n=\frac{1}{N}\sum _{k=0}^{N-1}{X}_k{e}^{\frac{2\pi i}{N}kn}n=0,\dots ,N-1.$

Retinotopic models in group-averaged data projected back into native space

Some text. Some analysis. Some figures.

Conclusions

Here is where you say what your results mean.

References - Resources and related work

References

Software

Appendix I - Code and Data

Code

File:CodeFile.zip

Data

zip file with my data

Appendix II - Work partition (if a group project)

Brian and Bob gave the lectures. Jon mucked around on the wiki.