2009 Max Halvorson - Revision history

imported>Psych 204: /* Conclusions */

2009-12-09T21:33:26Z

Conclusions

← Older revision		Revision as of 21:33, 9 December 2009
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	==hV4==		==hV4==
	In the areas of interest, specifically left and right hV4 near the sinus, Spin-Echo imaging did no better than Gradient-Echo imaging in gathering a coherent signal from hV4. Furthermore, surrounding areas have distortions in Spin-Echo scans which are absent in Gradient-Echo scans (Figure 8). It seems that Spin-Echo scans, at least in this case, provide no useful additional information about hV4.		In the areas of interest, specifically left and right hV4 near the sinus, Spin-Echo imaging did no better than Gradient-Echo imaging in gathering a coherent signal from hV4. Furthermore, surrounding areas have distortions in Spin-Echo scans which are absent in Gradient-Echo scans (Figure 8). It seems that Spin-Echo scans, at least in this case, provide no useful additional information about hV4.

			==Implications==
			Further research might examine other methods of obtaining functional data in this region (e.g. different pulse sequences). Also, other regions of the brain remain to be examined. Perhaps there are areas of (visual and non-visual) cortex in which Spin-Echo scans offer a distinct advantage.

	= References =		= References =

imported>Psych 204: /* Conclusions */

2009-12-09T21:28:56Z

Conclusions

← Older revision		Revision as of 21:28, 9 December 2009
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	= Conclusions =		= Conclusions =

			==Overall==
	At first glance, one notices the difference in overall signal and signal-to-noise between the two scans as indicated by the brighter colors in the Gradient-Echo scan and the greater contrast between areas of signal areas of no signal (Figure 2). Another striking difference is seen in the type of distortions caused by the ear canals in the Gradient-Echo (absence of signal in that area) and the Spin-Echo ("bubbles" of signal built up over that area) scans (Figure 3). Furthermore, the phase, as shown by the FFT of each scan, of the two signals is right in-sync, with both peaking at the same time (Figures 9 & 10).		At first glance, one notices the difference in overall signal and signal-to-noise between the two scans as indicated by the brighter colors in the Gradient-Echo scan and the greater contrast between areas of signal areas of no signal (Figure 2). Another striking difference is seen in the type of distortions caused by the ear canals in the Gradient-Echo (absence of signal in that area) and the Spin-Echo ("bubbles" of signal built up over that area) scans (Figure 3). Furthermore, the phase, as shown by the FFT of each scan, of the two signals is right in-sync, with both peaking at the same time (Figures 9 & 10).

imported>Psych 204: /* Conclusions */

2009-12-09T21:28:23Z

Conclusions

← Older revision		Revision as of 21:28, 9 December 2009
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	= Conclusions =		= Conclusions =

	At first glance, one notices the difference in overall signal and signal-to-noise between the two scans as indicated by the brighter colors in the Gradient-Echo scan and the greater contrast between areas of signal areas of no signal (Figure 2). Another striking difference is seen in the type of distortions caused by the ear canals in the Gradient-Echo (absence of signal in that area) and the Spin-Echo ("bubbles" of signal built up over that area) scans (Figure 3).		At first glance, one notices the difference in overall signal and signal-to-noise between the two scans as indicated by the brighter colors in the Gradient-Echo scan and the greater contrast between areas of signal areas of no signal (Figure 2). Another striking difference is seen in the type of distortions caused by the ear canals in the Gradient-Echo (absence of signal in that area) and the Spin-Echo ("bubbles" of signal built up over that area) scans (Figure 3). Furthermore, the phase, as shown by the FFT of each scan, of the two signals is right in-sync, with both peaking at the same time (Figures 9 & 10).

	The next thing to note is the overall similarity in signal and phase between the Spin-Echo and Gradient-Echo signals for V1-V3 (Figures 4 & 5). One also notices that the Spin-Echo scan has a much lower overall signal throughout. Though the Spin-Echo scans have a weaker signal, they seem to reflect similar data for most areas of visual cortex (analyses of cortex other than V1-V3 not shown). In areas like the ear canals where the distortions produced differ in character, Spin-Echo imaging doesn't do a better job either.		The next thing to note is the overall similarity in signal and phase between the Spin-Echo and Gradient-Echo signals for V1-V3 (Figures 4 & 5). One also notices that the Spin-Echo scan has a much lower overall signal throughout. Though the Spin-Echo scans have a weaker signal, they seem to reflect similar data for most areas of visual cortex (analyses of cortex other than V1-V3 not shown). In areas like the ear canals where the distortions produced differ in character, Spin-Echo imaging doesn't do a better job either.

imported>Psych 204: /* Results */

2009-12-09T21:08:43Z

Results

← Older revision		Revision as of 21:08, 9 December 2009
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	[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]		[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]

	[[File:Gradient_Echo_FFT.jpg \|thumb\|400px\|~~center~~\| (Figure 9) Gradient-Echo FFT]]		[[File:Gradient_Echo_FFT.jpg \|thumb\|400px\|left\| (Figure 9) Gradient-Echo FFT]]
	[[File:Spin_Echo_FFT.jpg \|thumb\|400px\|~~right~~\| (Figure 10) Spin-Echo FFT]]		[[File:Spin_Echo_FFT.jpg \|thumb\|400px\|center\| (Figure 10) Spin-Echo FFT]]

	= Conclusions =		= Conclusions =

imported>Psych 204: /* Results */

2009-12-09T21:08:23Z

Results

← Older revision		Revision as of 21:08, 9 December 2009
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	[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]		[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]

	[[File:Gradient_Echo_FFT.jpg \|thumb\|400px\|~~left~~\| (Figure 9) Gradient-Echo FFT]]		[[File:Gradient_Echo_FFT.jpg \|thumb\|400px\|center\| (Figure 9) Gradient-Echo FFT]]
	[[File:Spin_Echo_FFT.jpg \|thumb\|400px\|right\| (Figure 10) Spin-Echo FFT]]		[[File:Spin_Echo_FFT.jpg \|thumb\|400px\|right\| (Figure 10) Spin-Echo FFT]]

imported>Psych 204: /* Results */

2009-12-09T21:07:47Z

Results

← Older revision		Revision as of 21:07, 9 December 2009
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	[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]		[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]

	[[File:Gradient_Echo_FFT.jpg \|thumb\|400px\| (Figure 9) Gradient-Echo FFT]]		[[File:Gradient_Echo_FFT.jpg \|thumb\|400px\|left\| (Figure 9) Gradient-Echo FFT]]
	[[File:Spin_Echo_FFT.jpg \|thumb\|400px\| (Figure 10) Spin-Echo FFT]]		[[File:Spin_Echo_FFT.jpg \|thumb\|400px\|right\| (Figure 10) Spin-Echo FFT]]

	= Conclusions =		= Conclusions =

imported>Psych 204: /* Results */

2009-12-09T21:07:31Z

Results

← Older revision		Revision as of 21:07, 9 December 2009
Line 43:		Line 43:
	[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]		[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]

	[[File:Gradient_Echo_FFT.jpg \|thumb\|400px~~\|left~~\| (Figure 9) Gradient-Echo FFT]]		[[File:Gradient_Echo_FFT.jpg \|thumb\|400px\| (Figure 9) Gradient-Echo FFT]]
	[[File:Spin_Echo_FFT.jpg \|thumb\|400px~~\|center~~\| (Figure 10) Spin-Echo FFT]]		[[File:Spin_Echo_FFT.jpg \|thumb\|400px\| (Figure 10) Spin-Echo FFT]]

	= Conclusions =		= Conclusions =

imported>Psych 204: /* Results */

2009-12-09T21:07:00Z

Results

← Older revision		Revision as of 21:07, 9 December 2009
Line 42:		Line 42:

	[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]		[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]

			[[File:Gradient_Echo_FFT.jpg \|thumb\|400px\|left\| (Figure 9) Gradient-Echo FFT]]
			[[File:Spin_Echo_FFT.jpg \|thumb\|400px\|center\| (Figure 10) Spin-Echo FFT]]

	= Conclusions =		= Conclusions =

imported>Psych 204: /* Conclusions */

2009-12-09T20:14:43Z

Conclusions

← Older revision		Revision as of 20:14, 9 December 2009
Line 47:		Line 47:
	At first glance, one notices the difference in overall signal and signal-to-noise between the two scans as indicated by the brighter colors in the Gradient-Echo scan and the greater contrast between areas of signal areas of no signal (Figure 2). Another striking difference is seen in the type of distortions caused by the ear canals in the Gradient-Echo (absence of signal in that area) and the Spin-Echo ("bubbles" of signal built up over that area) scans (Figure 3).		At first glance, one notices the difference in overall signal and signal-to-noise between the two scans as indicated by the brighter colors in the Gradient-Echo scan and the greater contrast between areas of signal areas of no signal (Figure 2). Another striking difference is seen in the type of distortions caused by the ear canals in the Gradient-Echo (absence of signal in that area) and the Spin-Echo ("bubbles" of signal built up over that area) scans (Figure 3).

	The next thing to note is the overall similarity in signal and phase between the Spin-Echo and Gradient-Echo signals for V1-V3 (Figures 4 & 5). One also notices that the Spin-Echo scan has a much lower overall signal throughout. Though the Spin-Echo scans have a weaker signal, they seem to reflect similar data for most areas of visual cortex (analyses of cortex other than V1-V3 not shown).		The next thing to note is the overall similarity in signal and phase between the Spin-Echo and Gradient-Echo signals for V1-V3 (Figures 4 & 5). One also notices that the Spin-Echo scan has a much lower overall signal throughout. Though the Spin-Echo scans have a weaker signal, they seem to reflect similar data for most areas of visual cortex (analyses of cortex other than V1-V3 not shown). In areas like the ear canals where the distortions produced differ in character, Spin-Echo imaging doesn't do a better job either.

	==hV4==		==hV4==

imported>Psych 204: /* Appendix I - Code and Data */

2009-12-09T00:54:42Z

Appendix I - Code and Data

← Older revision		Revision as of 00:54, 9 December 2009
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	Winawer J, Horiguchi H, Sayres R, Amano K, Wandell BA. (In Press) Mapping hV4 and ventral occipital cortex: The venous eclipse. Journal of Vision.		Winawer J, Horiguchi H, Sayres R, Amano K, Wandell BA. (In Press) Mapping hV4 and ventral occipital cortex: The venous eclipse. Journal of Vision.

	~~= Appendix I - Code and Data =~~

	~~==Code==~~
	~~[[Media:MyCodeZipFile.zip \| zip file with code]]~~

	~~==Data==~~
	~~[[Media:MyDataZipFile.zip \| zip file with my data]]~~

← Older revision		Revision as of 21:08, 9 December 2009
Line 43:		Line 43:
	[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]		[[File:Sinus_ROI.jpg \|thumb\|400px\|center\| (Figure 8) Sinus ROI and nearby visual cortex]]

	[[File:Gradient_Echo_FFT.jpg \|thumb\|400px\|~~left~~\| (Figure 9) Gradient-Echo FFT]]		[[File:Gradient_Echo_FFT.jpg \|thumb\|400px\|center\| (Figure 9) Gradient-Echo FFT]]
	[[File:Spin_Echo_FFT.jpg \|thumb\|400px\|right\| (Figure 10) Spin-Echo FFT]]		[[File:Spin_Echo_FFT.jpg \|thumb\|400px\|right\| (Figure 10) Spin-Echo FFT]]