- Definition & common symptoms
- Most common lesion sites
- Temporo-parietal junction (TPJ) anatomy & function
November 21, 2014
5 questions you should be able to answer by the end of this presentation:
Hemispatial neglect
Hemineglect
Unilateral neglect
Spatial neglect
Hemiagnosia
Contralateral neglect
Unilateral visual inattention
Hemi-inattention
Neglect syndrome
Contralateral hemispatialagnosia
“A common and striking neuropsychological syndrome, in which patients fail to detect (and respond to) stimuli located contralaterally to a focal hemispheric lesion, even in the absence of primary sensory or motor deficits.”
Also reported as "critical lesion" sites: Posterior parietal cortex, angular gyrus, supramargnial gyrus, superior temporal gyrus, insula, dorsolateral and inferior frontal cortices
Also: thalamus, basal ganglia, white matter
Posner spatial cueing task (1980)
Circuit-breaker theory assumes that:
Circuit-breaker theory assumes that:
"the function of TPJ is to update internal models of the current behavioral context for the purpose of generating appropriate actions” – “particularly important when unexpected stimuli occur”!
TPJ takes new sensory info → updates the internal model of the environmental context → initiates appropriate action based on that update.
Accounts for TPJ activity in other domains!
Neglect patients also experience non-spatial symptoms such as:
2 components to neglect:
Neglect patients who are biased toward the right side of space won’t update their mental model based on sensory info from left side of space.
Rock, Paper, Scissor task: a non-spatial deficit in mental model updating
Is it paws-ible??
5 questions you should be able to answer by the end of this presentation:
5 questions you should be able to answer by the end of this presentation: