Basal Ganglia Lesions and the Theory of Fronto-Subcortical Loops: Neuropsychological Findings in Two Patients with Left Caudate Lesions

Abstract

Basal ganglia lesions have a high prevalence for associated behavioural impairments. However, the exact pattern of cognitive impairments and its relationship to individual basal ganglia lesion have rarely been investigated by means of a detailed neuropsychological and lesion study. Furthermore, different mechanisms have been proposed as relevant for the observed cognitive deficits; among these, the hypothesis of fronto-subcortical loops (Alexander et al., 1986) has made predictions regarding the relationship between the damage of particular striato-frontal circuits and the resulting behavioural impairment which await clinical confirmation. We present a study of two subjects who suffered a MRI-documented focal left basal ganglia hematoma. The two patients differed in their lesions; in one patient (PJ) large parts of the caudate nucleus were destroyed whereas in the other (AS) mainly the pallidum and putamen were lesioned and the caudate suffered only minor damage. In the acute phase, the behavioural and neuropsychological abnormalities were similar in both cases and included mainly abulia, an impairment of executive and attentional functions, and a severe amnestic syndrome. After several months many functions were restored in AS, whereas PJ's abilities remained largely defective. Based on these data and on previous case studies several conclusions are drawn. Left caudate lesions induce marked and long-lasting behavioural and neuropsychological impairments comprising predominantly drive, executive control, attention, and memory. The extent of lesion in the head of the caudate nucleus is the critical factor regarding the severity and the outcome of the syndrome, whereas damage to the putamen and pallidum is less crucial for cognitive functions. A subset of behavioural alterations, among them abulia, attentional and frontal-executive dysfunctions, can well be attributed to lesions of the anterior cingulate circuit and the dorsolateral-frontal circuit at the basal ganglia level. Other impairments, most importantly the prominent amnestic syndrome, are more difficult to interpret on the grounds of this hypothesis and may be related to other pathomechanisms.

Anatomical substrates and neurocognitive predictors of daily numerical abilities in mild cognitive impairment

“…In fact, if the intrinsic difficulty of the tasks were influencing the level of performance, one should expect that patients with other neurological conditions should also fail in this or in other similar tests. Rather, it is now well-established that different degenerative diseases show characteristic impairment profiles which follow particular lesional/degeneration patterns, such as in the case of Alzheimer disease (Carlomagno et al, 1999;Delazer, Karner, Proell & Benke, 2006;Helpern, McMilla, Moore, Dennis & Grossman, 2003;Martini, Domahs, Benke & Delazer, 2003;Zamarian et al, 2007b), Parkinson disease and other basal ganglia dysfunctions (Benke, Delazer, Bartha & Auer, 2003;Delazer et al, 2004;Tamura et al, 2003;Zamarian et al, 2006), semantic dementia (Cappelletti, Butterworth & Kopelman, 2001, 2012, amyothrophic lateral sclerosis (Palmieri et al, 2013), and genetic defects (e.g., Bertella et al, 2005;Semenza et al, 2008;Semenza et al, 2012). Each degenerative disease seems to affect aspects of number processing and calculation in a distinct way.…”

Functional Neuroanatomy and Behavioural Correlates of the Basal Ganglia: Evidence from Lesion Studies

“…Benke et al [15] discussed case reports of two patients, PJ (male, aged 56) and AS (female, aged 58), who had suffered from spontaneous left basal ganglia haematoma. In PJ the caudate nucleus was mainly affected, whilst in AS mainly the globus pallidus and putamen were affected with relatively minor damage to the caudate nucleus.…”

Auditory P300 Event-Related Potentials in Children with Sydenham?s Chorea

“…In most studies it is suggested that, there is an evidence of basal ganglia dysfunction which can be showed by morphologic and functional neuroimaging techniques 4 . Basal ganglia dysfunction can also present with cognitive impairment, characterized mainly by executive dysfunction 5 . So, it may be considered that degeneration of frontostriatal loops could lead not only to motor and behavioural changes but also to cognitive abnormalities in SC 6 .…”