Kaja Johnson - Revision history

imported>Psych204B: /* MT */

2010-03-20T02:52:57Z

← Older revision		Revision as of 02:52, 20 March 2010
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	== MT ==		== MT ==
	This served as an effective control condition. There were so particular significant selectivities for categories since this region responds to motion stimuli. However, the MT also seems to prefer peripheral stimuli over foveal ones as there were greater activations during these presentations.		This served as an effective control condition. There were so particular significant selectivities for categories since this region responds to motion stimuli. However, the MT also seems to prefer peripheral stimuli over foveal ones as there were greater activations during these presentations.
			<br>
			<br>
			<center>[[File:MT_ROIs.jpg \| MT ROIs]]

			<br>Left MT
			[[File:LH_MT_timecourse.jpg \| Left MT Results]]
			<br>Right MT
			[[File:RH_MT_timecourse.jpg \| Right MT Results]]
			</center>

	= Conclusions =		= Conclusions =

imported>Psych204B: /* RSc */

2010-03-20T02:51:25Z

RSc

← Older revision		Revision as of 02:51, 20 March 2010
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	== RSc ==		== RSc ==
	The left and rigth RSc regions do not appear to differentiate between foveal and periphery stimuli as the activity across locations showed only a main effect of category. However, this face-place distinction seems to occur in the periphery, as the activations were driven by the results seen when stimuli for faces and places were presented in peripheral locations.		The left and rigth RSc regions do not appear to differentiate between foveal and periphery stimuli as the activity across locations showed only a main effect of category. However, this face-place distinction seems to occur in the periphery, as the activations were driven by the results seen when stimuli for faces and places were presented in peripheral locations.
			<br>
			<br>
			<center>[[File:RSc_ROIs.jpg \| RSc ROIs]]

			<br>Left RSc
			[[File:LH_RSc_timecourse.jpg \| Left RSc Results]]
			<br>Right PPA
			[[File:RH_RSc_timecourse.jpg \| Right RSc Results]]
			</center>

	== MT ==		== MT ==

imported>Psych204B: /* PPA */

2010-03-20T02:48:46Z

PPA

← Older revision		Revision as of 02:48, 20 March 2010
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	== PPA ==		== PPA ==
	The left and right PPAs showed selectivity for peripherally presented stimuli across categories. Again, it maintained expected selectivity for places controlling for location of the presentation.		The left and right PPAs showed selectivity for peripherally presented stimuli across categories. Again, it maintained expected selectivity for places controlling for location of the presentation.
			<br>
			<br>
			<center>[[File:PPA_ROIs.jpg \| PPA ROIs]]

			<br>Left PPA
			[[File:LH_PPA_timecourse.jpg \| Left PPA Results]]
			<br>Right PPA
			[[File:RH_PPA_timecourse.jpg \| Right PPA Results]]
			</center>

	== RSc ==		== RSc ==

imported>Psych204B: /* OFA */

2010-03-20T02:47:10Z

OFA

← Older revision		Revision as of 02:47, 20 March 2010
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	== OFA ==		== OFA ==
	The left and right OFAs show selectivity for faces, however it appears the lOFA is particularly selective for foveal stimuli in general, including places (there was more activation for foveal places than peripheral places), while the rOFA is particularly selective for peripheral stimuli (again, a main effect of location was seen with more activation for both faces and places in the periphery).		The left and right OFAs show selectivity for faces, however it appears the lOFA is particularly selective for foveal stimuli in general, including places (there was more activation for foveal places than peripheral places), while the rOFA is particularly selective for peripheral stimuli (again, a main effect of location was seen with more activation for both faces and places in the periphery).
			<br>
			<br>
			<center>[[File:OFA_ROIs.jpg \| OFA ROIs]]

			<br>Left OFA
			[[File:LH_OFA_timecourse.jpg \| Left OFA Results]]
			<br>Right OFA
			[[File:RH_OFA_timecourse.jpg \| Right OFA Results]]
			</center>

	== PPA ==		== PPA ==

imported>Psych204B: /* FFA */

2010-03-20T02:45:28Z

FFA

← Older revision		Revision as of 02:45, 20 March 2010
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	<br>Right FFA		<br>Right FFA
	[[File:RH_FFA_timecourse.jpg \| Right FFA Results]]		[[File:RH_FFA_timecourse.jpg \| Right FFA Results]]
			</center>

	== OFA ==		== OFA ==

imported>Psych204B: /* FFA */

2010-03-20T02:45:11Z

FFA

← Older revision		Revision as of 02:45, 20 March 2010
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	<br>		<br>
	<br>		<br>
	[[File:FFA_ROIs.jpg \| ~~Left~~ FFA]]		<center>[[File:FFA_ROIs.jpg \| FFA ROIs]]
	[[File:LH_FFA_timecourse.jpg \| Left FFA]]
			<br>Left FFA
			[[File:LH_FFA_timecourse.jpg \| Left FFA Results]]
			<br>Right FFA
			[[File:RH_FFA_timecourse.jpg \| Right FFA Results]]

	== OFA ==		== OFA ==

imported>Psych204B: /* FFA */

2010-03-20T02:39:38Z

FFA

← Older revision		Revision as of 02:39, 20 March 2010
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	<br>		<br>
	<br>		<br>
	[[File:~~Example~~.jpg]]		[[File:FFA_ROIs.jpg \| Left FFA]]
	[[File:~~Example~~.jpg]]		[[File:LH_FFA_timecourse.jpg \| Left FFA]]

	== OFA ==		== OFA ==

imported>Psych204B: /* FFA */

2010-03-20T02:36:57Z

FFA

← Older revision		Revision as of 02:36, 20 March 2010
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	== FFA ==		== FFA ==
	In the left hemisphere of the brain, the FFA appears to be particularly selective for foveally presented stimuli of faces, and processes peripheral presentations of faces similarly to that of place stimuli. This implies that the left FFA is more specifically selective for faces presented in particular areas of the visual field, and not faces indiscriminately. The right FFA did not reveal any differences across all stimuli and did not show any selectivity for places, however it is often the case that this selectivity is localized to one hemisphere.		In the left hemisphere of the brain, the FFA appears to be particularly selective for foveally presented stimuli of faces, and processes peripheral presentations of faces similarly to that of place stimuli. This implies that the left FFA is more specifically selective for faces presented in particular areas of the visual field, and not faces indiscriminately. The right FFA did not reveal any differences across all stimuli and did not show any selectivity for places, however it is often the case that this selectivity is localized to one hemisphere.
			<br>
			<br>
			[[File:Example.jpg]]
			[[File:Example.jpg]]

	== OFA ==		== OFA ==

imported>Psych204B at 02:33, 20 March 2010

2010-03-20T02:33:23Z

← Older revision		Revision as of 02:33, 20 March 2010
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	= Results =		= Results =
			As expected the foveal presentations of face and place stimuli in all ROIs follow findings of previous research as stimuli in studies are traditionally only presented in the fovea. Face-selective areas showed greater activity when presented with faces than with places, and the reverse is true for place-selective areas.

	== ~~Retinotopic models in native space~~ ==		== FFA ==
	~~Some text~~. ~~Some analysis~~. ~~Some figures~~.		In the left hemisphere of the brain, the FFA appears to be particularly selective for foveally presented stimuli of faces, and processes peripheral presentations of faces similarly to that of place stimuli. This implies that the left FFA is more specifically selective for faces presented in particular areas of the visual field, and not faces indiscriminately. The right FFA did not reveal any differences across all stimuli and did not show any selectivity for places, however it is often the case that this selectivity is localized to one hemisphere.

	== ~~Retinotopic models in individual subjects transformed into MNI space~~ ==		== OFA ==
	~~Some text. Some analysis. Some figures~~.		The left and right OFAs show selectivity for faces, however it appears the lOFA is particularly selective for foveal stimuli in general, including places (there was more activation for foveal places than peripheral places), while the rOFA is particularly selective for peripheral stimuli (again, a main effect of location was seen with more activation for both faces and places in the periphery).

	== ~~Retinotopic models in group-averaged data on the MNI template brain~~ ==		== PPA ==
	~~Some text~~. ~~Some analysis. Some figures. Maybe some equations~~.		The left and right PPAs showed selectivity for peripherally presented stimuli across categories. Again, it maintained expected selectivity for places controlling for location of the presentation.


	==~~= Equations=~~==		== RSc ==
	~~If you want~~ to ~~use equations, you can use~~ the ~~same formats that are use on wikipedia~~. ~~<br>~~		The left and rigth RSc regions do not appear to differentiate between foveal and periphery stimuli as the activity across locations showed only a main effect of category. However, this face-place distinction seems to occur in the periphery, as the activations were driven by the results seen when stimuli for faces and places were presented in peripheral locations.
	~~''See wikimedia help on~~ ~~[http://meta.wikimedia.org/wiki/Help:Displaying_a_formula formulas]~~ for ~~help.'' <br>~~
	~~This example of equation use is copied~~ and ~~pasted from [http://en.wikipedia.org/wiki/Discrete_Fourier_transform wikipedia's article on the DFT]~~.

	The [[sequence]] of ''N'' [[complex number]]s ''x''<sub>0</sub>, ..., ''x''<sub>''N''−1</sub> is transformed into the sequence of ''N'' complex numbers ''X''<sub>0</sub>, ..., ''X''<sub>''N''−1</sub> by the DFT according to the formula:

	~~:<math>X_k = \sum_{n=0}^{N-1} x_n e^{-\frac{2 \pi i}{N} k n} \quad \quad k = 0, \dots, N-1</math>~~

	where i is the imaginary unit and <math>e^{\frac{2 \pi i}{N}}</math> 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''<sub>''k''</sub> can thus be viewed as coefficients of ''x'' in an [[orthonormal basis]].)

	The transform is sometimes denoted by the symbol <math>\mathcal{F}</math>, as in <math>\mathbf{X} = \mathcal{F} \left \{ \mathbf{x} \right \} </math> or <math>\mathcal{F} \left ( \mathbf{x} \right )</math> or <math>\mathcal{F} \mathbf{x}</math>.

	~~The '''inverse discrete Fourier transform (IDFT)''' is given by~~

	~~:<math>x_n = \frac{1}{N} \sum_{k=0}^{N-1} X_k e^{\frac{2\pi i}{N} k n} \quad \quad n = 0,\dots,N-1.</math>~~

	~~== Retinotopic models in group-averaged data projected back into native space ==~~
	~~Some text. Some analysis. Some figures.~~

			== MT ==
			This served as an effective control condition. There were so particular significant selectivities for categories since this region responds to motion stimuli. However, the MT also seems to prefer peripheral stimuli over foveal ones as there were greater activations during these presentations.

	= Conclusions =		= Conclusions =
			Localization for specialized processing generally follows expectations based on functionality in the external world. For example, it makes sense for the MT to be selective for peripheral stimuli and motion stimuli, because it will be most adaptive to quickly respond to potentially dangerous objects coming rapidly from surprise areas to your sides (e.g. an oncoming lion or fist). Likewise, face-selective areas specialize for foveal processing due to the need to focus attention on central details of the visual field. Place-selective areas specialize for peripheral processing due to the need to focus on details located on all parts of the visual field for accurate recognition. Results in the right hemisphere across categories of faces and places seemed to prefer peripheral processing which contradicts the original hypotheses. This, however, makes sense as the right side of the brain is also known to specialize in spatial processing, so movement and place are important areas of focus for activities that require spatial skills. The findings also implicate the RSc as a possible area where general processing of peripheral visual stimuli occurs, which may contribute specificity to the function of this region.
			<br><br>
			The limitation of this study is of course the small number of subjects examined. In order to generalize these results, replication must be done in a larger pool of participants.

	~~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==~~		= References =
	~~[[File:DataFile.zip \| zip file with my data]]~~

	~~= Appendix II - Work partition~~ (if a ~~group project~~) =		Epstein, R., Harris, A., Stanley, D. and Kanwisher, N., 1999. The parahippocampal place area: recognition, navigation, or encoding?. Neuron 23, pp. 115–125.
	~~Brian~~ and ~~Bob gave~~ the ~~lectures~~. ~~Jon mucked around on~~ the ~~wiki~~.		<br>Epstein RA, Parker WE, Feiler AM (2007) Where am I now? Distinct roles for parahippocampal and retrosplenial cortices in place recognition. J Neurosci 27:6141–6149.
			<br>Gauthier I, Trends Cognit. Sci. 4, 1 (2000)
			<br>Kanwisher N, McDermott J, Chun MM (1997 Jun 1). "The fusiform face area: a module in human extrastriate cortex specialized for face perception". J Neurosci. 17 (11): 4302–11.
			<br>Latham K., Whitaker D. A comparison of word recognition and reading performance in foveal and peripheral vision (1996) Vision Research, 36 (17), pp. 2665-2674.
			<br>Peripheral Vision. (n.d.). WebExhibits. Retrieved March 16, 2010, from http://www.webexhibits.org/colorart/ag.html
			<br>Pitcher D, Walsh V, Yovel G, Duchaine B. TMS evidence for the involvement of the right occipital face area in early face processing. Curr Biol doi:10.1016/j.cub.2007.07.063, 2007.
			<br>Vann S.D., Wilton L.A.K., Muir J.L., Aggleton J.P. Testing the importance of the caudal retrosplenial cortex for spatial memory in rats (2003) Behavioural Brain Research, 140 (1-2), pp. 107-118.

imported>Psych204B at 02:07, 20 March 2010

2010-03-20T02:07:03Z

← Older revision		Revision as of 02:07, 20 March 2010
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	<br>		<br>
	<br>		<br>
	[[File:~~C:\Users\Kaja Johnson\Desktop\Winter 2010\Psych 204B\edited_images\~~hrf_design.jpg]]		[[File:hrf_design.jpg \| Figure 1]]

	=== MR Analysis ===		=== MR Analysis ===