Cerebellar Functional Lateralization From the Perspective of Clinical Neuropsychology

Abstract

Objective: The cerebellar functional laterality, with its right hemisphere predominantly involved in verbal performance and the left one engaged in visuospatial processes, has strong empirical support. However, the clinical observation and single research results show that the damage to the right cerebellar hemisphere may cause extralinguistic and more global cognitive decline. The aim of our research was to assess the pattern of cognitive functioning, depending on the cerebellar lesion side, with particular emphasis on the damage to the right cerebellar hemisphere.Method: The study sample consisted of 31 patients with focal cerebellar lesions and 31 controls, free of organic brain damage. The Addenbrooke’s Cognitive Examination ACE III and the Trail Making Test TMT were used to assess patients’ cognitive functioning.Results: Left-sided cerebellar lesion patients scored lower than controls in attention and visuospatial domain, but not in language, fluency, and memory functions. Participants with right-sided cerebellar lesion demonstrated a general deficit of cognitive functioning, with impairments not only in language and verbal fluency subscales but also in all ACE III domains, including memory, attention, and visuospatial functions. The TMT results proved that cerebellar damage is associated with executive function impairment, regardless of the lesion side.Conclusion: The cognitive profiles of patients with cerebellum lesions differ with regard to the lesion side. Left-sided cerebellar lesions are associated with selective visuospatial and attention impairments, whereas the right-sided ones may result in a more global cognitive decline, which is likely secondary to language deficiencies, associated with this lateral cerebellar injury.

The cerebellum and cognitive neural networks

“…The Addenbrooke's Cognitive Test ACE III and the Pathway Test TMT were used to assess cognitive function in 31 patients with localized cerebellar lesions and 31 healthy volunteers. It was discovered that patients with left-sided cerebellar lesions were impaired in the attention and visuospatial domains, while patients with right-sided cerebellar damage had deficits in general cognitive function (Starowicz-Filip et al, 2021). The research by Baillieux also confirmed that the left cerebellum controlled attention and 10.3389/fnhum.2023.1197459 visuospatial skills, but it was also thought that the right cerebellar hemisphere influenced logical thinking and language processing skills (Baillieux et al, 2010).…”

Quantitative brain morphometry identifies cerebellar, cortical, and subcortical gray and white matter atrophy in late‐onset Tay‐Sachs disease

“…It is also possible to speculate that the observed asymmetric cerebellar atrophy may be related to speech abnormalities, as studies on functional lateralization of the cerebellum indicate the role of the right cerebellar hemisphere in language and speech processing. 47 Several study limitations need to be mentioned. First, quantitative assessment of clinical severity was not available for most patients, precluding clinical phenotype and brain-morphometry correlation analyses.…”

“…One may speculate that abnormal development of cerebellar and cortical motor circuits underlies developmental stutter in LOTS patients. It is also possible to speculate that the observed asymmetric cerebellar atrophy may be related to speech abnormalities, as studies on functional lateralization of the cerebellum indicate the role of the right cerebellar hemisphere in language and speech processing 47 …”

Disrupted topological properties of the structural brain network in patients with cerebellar infarction on different sides are associated with cognitive impairment

“…( 1 , 22 , 23 ). Some studies have also shown that the cerebellum may show laterality in cognition; that is, the left cerebellum is mainly related to visuospatial function ( 24 ), while the right cerebellum is mainly related to executive function ( 25 ).…”