Cerebellar lingula size and experiential risk factors associated with high levels of alcohol and drug use in young adults

Abstract

Previous studies have reported cerebellar abnormalities or static ataxia associated with risk for chronic use of alcohol and drugs. Adverse childhood experience is another strong risk factor for later substance abuse. We therefore sought to ascertain the relationship between morphological phenotypes of the lingula (lobule I) of the anterior cerebellar vermis, and exposure to emotional (EM) versus physical (PM) maltreatment, on the degree of ongoing alcohol or drug use. The study design consisted of a cross-sectional in vivo neuroimaging study, utilizing retrospective assessment of maltreatment history and self-reports of alcohol and substance use. Study participants were 153 subjects (54 M/99F, 21.9 +/- 2.2 years) selected for imaging from a database of 1,402 community participants 18-25 years of age, who completed a detailed online screening instrument and met rigorous inclusion/exclusion criteria. Subjects were exposed to only physical abuse or harsh corporal punishment (HCP; PM group, n = 37) and parental verbal abuse and/or witnessing domestic violence (EM group, n = 58) or had no history of maltreatment or axis I disorders (n = 58). The main outcome measures consisted of the gray matter volume of lobule I as measured by manual tracing, number and type of alcoholic beverages consumed during a drinking session, number of sessions per month, and monthly drug use, along with family history of drug and alcohol abuse. Lingula thickness was not attenuated by alcohol use or maltreatment history. However, increased lingula thickness was associated with greater consumption of drugs and hard liquor, particularly in physically maltreated subjects who consumed 2.5- and 2.7-fold more alcohol and used drugs 6.1- and 7.8-fold more frequently than controls or EM subjects, respectively. In conclusion, physical maltreatment was observed to interact with cerebellar morphology resulting in a strong association with alcohol and substance use. Lingula thickness may represent a novel, experientially sensitive, phenotypic risk factor for enhanced alcohol and drug use that perhaps modulates sensitivity to these agents.

Figure 1

Hand tracing of Larsell’s (14) Figure 54 of medial sagittal sections of adult anterior cerebellum which according to Larsell represented “gradations in the central lobule and lingual that have significance when compared with the vermian segments between the preculminate fissure and the anterior meduallary velum of the subhuman cerebella and with the development of this part of the vermis in man. p. 40–41.” Parts A-E of this figure illustrate the unfused thin variations of lobule I with a distinctive lobule II presentation. Parts F-I of the figure illustrate the fusing of lobule I+II common in our sample. Hatching in the figure illustrate typical sampling of the lingual in these hypothetical cases.

Figure 2

Common phenotypes of the anterior lobes of the cerebellar vermis. Adult anterior cerebellar vermis (A) hand traced from (14) p. 41, Figure 54A & H) depicting the normal thin phenotype of lobule I and typical lobule II (left) and the normal thick phenotype (right) lacking a discrete lobule II. It appears that the folia of the missing lobule II have migrated to lobule I; thus Larsell’s use of the term “lobule I+II”. The presence (left) or absence (right) of the precentral fissure a (f.prc.a) which was described by Larsell (14) (p. 18) as the defining characteristic of a thin lobule I with normal lobule II. (B) Sagittal T2-weighted matched turbo spin echo images of individuals displaying thick lobules. (C) T2-relaxation time maps collected in the same plane as A, illustrating the ROI placement on lobule I.