Wednesday, April 9, 2014

Paper Review: Acute immobilisation facilitates premotor preparatory activity for the non-restrained hand when facing grasp affordances

Acute immobilisation facilitates premotor preparatory activity for the non-restrained hand when facing grasp affordances.

Simone Kühn, Anika Werner, Ulman Lindenberger, Julius Verrel

NeuroImage, Springer - online


Use and non-use of body parts during goal-directed action are major forces driving reorganisation of neural processing. We investigated changes in functional brain activity resulting from acute short-term immobilisation of the dominant right hand. Informed by the concept of object affordances, we predicted that the presence or absence of a limb restraint would influence the perception of graspable objects in a laterally specific way.  Twenty-three participants underwent fMRI scanning during a passive object-viewing task before the intervention as well as with and without wearing an orthosis. The right dorsal premotor cortex and the left cerebellum were more strongly activated when the handle of an object was oriented towards the left hand while the right hand was immobilised compared with a situation where the hand was not immobilised. The cluster in the premotor cortex showing an interaction between condition (with restraint, without restraint) and stimulus action side (right vs. left) overlapped with the general task vs. baseline contrast prior to the intervention, confirming its functional significance for the task.  These results show that acute immobilisation of the dominant right hand leads to rapid changes of the perceived affordance of objects. We conclude that changes in action requirements lead to almost instantaneous changes in functional activation patterns, which in turn may trigger structural cortical plasticity.

This is another indicator of the effect of viewing objects in an orientation over planning behaviour in the brain (I assume this effect will modulate planning behaviours in humans, though they only indicate that the FMRI scan is affected).

I would like to see a follow up experiment that utilises cognitive talk-aloud protocols, in a similar manner to this review -  This would give credence to the possibility that objects presented in a virtual world enable users to talk about them more.

So, could the presentation of the objects kick off memories of previous process models, or could it also enable a person to create a better plan for future process models, as this goal directed behaviour may be future directed in an unpracticed manner.  Could the virtual world visualisations affect both the planning for future and the memory of the past, due to the evocation of spatial manipulation tasks in the world.

Could this be that even for business tasks, the situating of the person at the desk changes the planning behaviour?!?!?  I have to admit, that I often feel motivated when I hit my desk at work, not before or after.  The work place has an effect on me, and my goal setting state; more than my boss. ;-)

Interesting to note the neuro plasticity affects of this experiment, in an almost instant manner.  The effects are available instantly, with no training.  In this experiment, they only know they cannot move their hand, it is not really immobilised, and yet the effect takes place.

Would be interesting to note how immersion affects the perception of synthetic objects in this manner, and how it would work in an Occulus.

They cite a paper showing that wrestlers are superior in spatial rotation estimation, but only when their hands are unrestrained.  When their hands are restrained, they lose this ability.  This means that they potentially, are simulating the actions in their brain.  This adds further weight to the argument that cognitive processes are situated in bodily actions, and stored in such a manner in our brains.


Moreau, D., 2013. Constraining movement alters the recruitment of motor processes in 433 mental rotation. Exp. Brain Res. 224, 447–454.

Wednesday, April 2, 2014

Paper Review: The effect of priming pictures and videos on a question-answer dialog scenario in a virtual environment

#Title#The effect of priming pictures and videos on a question-answer dialog scenario in a virtual environment.
#Authors#Qu, C., Brinkman, W.-P., Wiggers, P., & Heynderickx, I.
#Venue#Presence Teleoperators and Virtual Environments, 22(2), 91-109


Having a free speech conversation with avatars in a virtual environment can be desirable in
virtual reality applications such as virtual therapy and serious games. However, recognizing and
processing free speech seems too ambitious to realize with the current technology. As an
alternative, pre-scripted conversations with keyword detection can handle a number of
goal-oriented situations as well as some scenarios in which the conversation content is of
secondary importance. This is, for example, the case in virtual exposure therapy for the
treatment of people with social phobia, where conversation is for exposure and anxiety arousal
only. A drawback of pre-scripted dialog is the limited scope of user’s answers. The system cannot
handle a user’s response, which does not match the pre-defined content, other than by providing
a default reply. A new method which uses priming material to restrict the possibility of the
user’s response is proposed in this paper to solve this problem. Two studies were conducted to
investigate whether people can be guided to mention specific keywords with video and/or picture
primings. Study 1 was a two by two experiment in which participants (n = 20) were asked to
answer a number of open questions. Prior to the session, participants watched priming videos or
unrelated videos. During the session, they could see priming pictures or unrelated pictures on a
whiteboard behind the person who asked the questions. Results showed that participants tended
to mention more keywords both with priming videos and pictures. Study 2 shared the same
experimental setting but was carried out in virtual reality instead of in the real world.
Participants (n = 20) were asked to answer questions of an avatar when they were exposed to
priming material before and/or during the conversation session. The same results were found:
the surrounding media content had a guidance effect. Furthermore, when priming pictures
appeared in the environment, people sometimes forgot to mention the content they typically
would mention.


Keyword dialogs with priming as pragmatic solution to NLP short comings.

Seeks to use the virtual world to give an illusion of free will, ironically, primed by visual content.  What does this say about our sense of free will.  Hmmmm.

Useful social phobia application, doe it hold that visual priming will work when obtaining information from experts in the field?  I think it does, due to the obvious priming effect.  If the avatar is an expert, then one can surmise that a person in the world could use the virtual world priming to provoke relevant questions in world, and extract better information from the participant in the interview.

They state they are the first in this place; my work on this topic is a close second! Yay!

VRET is considered as good as "in-vivo"; I prefer the word "in-situ" from my perspective.

They do not seem to be across the latest developments in NLP and speech recog.; their main citation is from 2000!

Igroup Presence Questionnaire (IPQ) (Schubert, Friedmann, & Regenbrecht, 2001). can be used to assess immersion levels for effects by oculus rifts etc. with an online database for comparison - NOTE THIS FOR FUTURE WORK!

They have found a significant effect with priming via images and videos - more keywords were mentioned with real setting and with virtual setting.  Results were significant.

Note, their results are with an immersive HMD; need to see if effects transfer to less immersive environments such as laptops, tablets etc.  Would be an interesting experiment.

They note issues with the lack of realism of the virtual world, and its possible noise effect on the differences.  However, one would assume that a poorly modelled world giving a good outcome for this work should indicate that the realism is above threshold for the priming effect.

They found that people still gave common answers to questions, even with the priming effects with videos.  Pictures seemed to suppress common answers from the participants.


So, from my perspective, this work supports strongly the idea that conversations can be affected by the priming effect of virtual world content.  Thus, I can hypothesise that using virtual worlds for process model elicitation should be positively affected by a representation of the interviewee's workplace.  The expected priming effects should occur.

Slater, M. (2009). Place illusion and plausibility can lead to realistic behaviour in immersive virtual environments. Philosophical Transactions of the Royal Society of London - Series B: Biological Sciences, 364 (1535), 3549–3557.

Pena, J., Hancock, J. T., & Merola, N. a. (2009, September). The Priming E↵ects of Avatars in Virtual Settings. Communication Research, 36 (6), 838–856.
Schubert, T., Friedmann, F., & Regenbrecht, H. (2001). The Experience of Presence: Factor Analytic Insights. Presence Teleoperators Virtual Environments, 10 (3), 266–281.