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Unformatted text preview: le (via posterior parts of the middle longitudi
ciculus [MdLF] and EmC/IOF). Involvement of these connec • Definition: Spatial neglect is a “failure
to report, respond, or orient to novel
or meaningful stimuli presented to the
side oppo- site the brain lesion when
this failure cannot be attributed to
either sensory or motor
defects” (Heilman et al. 1993)
• Shifted egocentre, deviated
spontaneous eye & head
network for spatial neglect
deﬁcit, studies based on structural brain imaging
• Unaware of shifted egocentre the individuals are unaware of their shifted spatial eg
ajor cortical areas straddling the sylvian ﬁssure: ietal junction (TPJ) and inferior parietal lobule
et al., 2010; Heilman et al., 1983; Karnath, Rennig,
rden, 2011; Mort et al., 2003; Rengachary, He, Fig. 1. (a) Example of the spontaneous eye and head orientation o
and waiting. The patients typically orient eyes and head toward t
situated on the right side. However, the room was empty with only
The eye-in-head deviation is even evident on the clinical brain scans
associated with spatial neglect rather than with brain damage per
of a group of 12 patients with spatial neglect (upper panel) during
patients without neglect (lower panel). The neglect patients show a
Fruhmann-Berger, Johannsen, & Karnath, 2008). (eye and head) default position. Despite variations in
of cognitive tasks, this spontaneous behavior appears
consistent and suggests that there is a unitary, homo
deﬁcit which we deﬁne as “spatial neglect” (illustrate What is spatial neglect?
• Neglect patients
have trouble with
writing and drawing
• May shave only one
side of the face, or
dress only the right
side of their body
• Line bisection?
neglect = attentional deficit?
or neglect = deficit of spatial awareness
=> attentional deficit Mesulam, 2000 46 What is spatial neglect?
Neglect patients have NO trouble with voluntary eye
• Neglect patients search only on the
A Q N Voluntary
Search Task A P K A R D Y A O T
L A I L O O F N P K P R D Y M
T H O E I L
J L O
C G F V
L F SK UZ O Y F N R D
X S X K
N Y E
W C B
Q C I
Z R B U V N E H U G I
V S F J Q O S WP Rightward P A G Z M Leftward B A Stimulus-driven
search task A H T W Y I A right side but voluntary saccades are
the same in both direction...
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This note was uploaded on 04/11/2012 for the course NEURO NROC64 taught by Professor Matthias during the Winter '12 term at University of Toronto- Toronto.
- Winter '12