Suppressing visual hallucinations in an adolescent by occipital transcranial magnetic stimulation: A single-case experimental research design

We present neuropsychological and transcranial magnetic stimulation (TMS) evidence with normal readers, that the effects of case mixing and contrast reduction on word identification are qualitatively different. Lesions and TMS applied to the right parietal lobe selectively disrupted the identification of mixed relative to single-case stimuli. Bilateral lesions and TMS applied to the occipital cortex selectively disrupted the identification of low-contrast words. These data suggest that different visual distortions (case mixing, contrast reduction) exert different effects on reading, modulated by contrasting brain regions. Case mixing is a “special” distortion and involves the recruitment of processes that are functionally distinct, and dependent on different regions in the brain, from those required to deal with contrast reduction.

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The therapeutic role of repetitive transcranial magnetic stimulation (rTMS) in parkinsonian visual hallucinations: Electrophysiological correlates

Journal of Clinical Neuroscience ◽

10.1016/j.jocn.2019.08.002 ◽

2019 ◽

Vol 69 ◽

pp. 281-284 ◽

Cited By ~ 3

Author(s):

Taha Hanoğlu ◽

Lütfü Hanoğlu ◽

Bahar Güntekin ◽

Tuba Aktürk ◽

Burak Yulug

Keyword(s):

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Repetitive Transcranial Magnetic Stimulation ◽

Visual Hallucinations ◽

Therapeutic Role

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Visual hallucinations in dementia with Lewy bodies: transcranial magnetic stimulation study

The British Journal of Psychiatry ◽

10.1192/bjp.bp.110.090373 ◽

2011 ◽

Vol 199 (6) ◽

pp. 492-500 ◽

Cited By ~ 40

Author(s):

John-Paul Taylor ◽

Michael Firbank ◽

Nicola Barnett ◽

Sarah Pearce ◽

Anthea Livingstone ◽

...

Keyword(s):

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Dementia With Lewy Bodies ◽

Cortical Excitability ◽

Lewy Bodies ◽

Visual Hallucinations ◽

Visual Responses ◽

People With Dementia ◽

Visual Cortical ◽

The Relationship

BackgroundThe aetiology of visual hallucinations is poorly understood in dementia with Lewy bodies. Pathological alterations in visual cortical excitability may be one contributory mechanism.AimsTo determine visual cortical excitability in people with dementia with Lewy bodies compared with aged-matched controls and also the relationship between visual cortical excitability and visual hallucinations in dementia with Lewy bodies.MethodVisual cortical excitability was determined by using transcranial magnetic stimulation (TMS) applied to the occiput to elicit phosphenes (transient subjective visual responses) in 21 patients with dementia with Lewy bodies and 19 age-matched controls.ResultsPhosphene parameters were similar between both groups. However, in the patients with dementia with Lewy bodies, TMS measures of visual cortical excitability correlated strongly with the severity of visual hallucinations (P = 0.005). Six patients with dementia with Lewy bodies experienced visual hallucination-like phosphenes (for example, seeing people or figures on stimulation) compared with none of the controls (P = 0.02).ConclusionsIncreased visual cortical excitability in dementia with Lewy bodies does not appear to explain visual hallucinations but it may be a marker for their severity.

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