How Does Alcohol Affect the Brain?

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Although ventricular size increases with each binge EtOH exposure, there is rapid recovery during each week of abstinence (Zahr et al. 2015). Such studies suggest that EtOH alone, at least in the exposure protocols evaluated with MRI, does not result in the characteristics observed in human alcoholics. Conversely, rats exposed to vaporized EtOH during adolescence are reported to show persistent effects (i.e., ventricular enlargement and deficits in hippocampal volume) into adulthood (Ehlers et al. 2013; Gass et al. 2014). Mice exposed to EtOH during adolescence are similarly purported to exhibit long-lasting regional brain-volume deficits in the olfactory bulb and basal forebrain (Coleman et al. 2011, 2014). These results suggest that the adolescent rodent brain may be more vulnerable to enduring toxic effects of EtOH than the adult rodent brain.

Health Topics: Alcohol and the Brain

The DS response in the heavy drinkers suggests the initiation of a shift from experimental to compulsive alcohol use during which a shift in neural processing is thought to occur from VS to DS control [103]. However, such cross-sectional studies are unable to establish whether such differences are prodromal or consequential of alcohol exposure. A recent longitudinal study in adolescents showed that blunted BOLD response to non-drug reward was predictive of subsequent problematic alcohol use [104]. These results suggests that certain functional differences in reward processing may predate problematic alcohol consumption. There is a longstanding notion that alcohol has an interactive effect on the biological aging processes, whereby the brains of alcohol dependent individuals resemble those of chronologically older individuals who do not have alcohol dependence [32].

Accumulation of oxidatively damaged proteins

Short-term (6 weeks) abstinence seems sufficient to observe some brain-volume recovery but does not result in equivalent brain volumes between recovering chronic alcoholics and healthy controls (Mann et al. 2005). That is, older alcoholics exhibit reduced ecstasy withdrawal and detox capacity for recovery compared with younger alcoholics (Fein et al. 1990; Munro et al. 2000; Reed et al. 1992; Rourke and Grant 1999). Some brain damage, such as neuronal loss (Harper 2007), may be irreversible, even with extended abstinence.

What to know about alcohol and brain damage

  1. In addition to reducing ventricular enlargement, rasagiline appeared to ameliorate the effects of thiamine deficiency on the FA decrease in the thalamus (Dror et al. 2014).
  2. These include your age, gender, overall health, body weight, how much you drink, how long you have been drinking and how often you normally drink.
  3. Alcohol can disrupt fetal development at any stage during a pregnancy—including at the earliest stages and before a woman knows she is pregnant.

Although alcohol can cause significant brain damage, an emerging body of research suggests that modest alcohol consumption may be beneficial for the brain. Severe head injuries may even be fatal because they affect the brain’s ability to control essential functions, such as breathing and blood pressure. Korsakoff syndrome often appears after an episode of Wernicke’s encephalopathy, which is acute alcohol-related brain dysfunction. Together, medication and behavioral health treatments can facilitate functional brain recovery. In short, alcohol use during adolescence can interfere with structural and functional brain development and increase the risk for AUD not only during adolescence but also into adulthood.

To better characterize brain function and behavior following exposure to alcohol both acute and chronic, as well as improve treatment outcome and reduce risk of relapse, it is imperative that large-scale studies with longitudinal designs are conducted. Remarkable developments in neuroimaging techniques have made it possible to study anatomical, functional, and biochemical changes in the brain that are caused by chronic alcohol use. Because of their precision and versatility, these techniques are invaluable for studying the extent and the dynamics of brain damage induced by heavy drinking. Because a patient’s brain can be scanned on repeated occasions, clinicians and researchers are able to track a person’s improvement with abstinence and deterioration with continued abuse. Furthermore, brain changes can be correlated with neuropsychological and behavioral measures taken at the same time. Brain imaging can aid in identifying factors unique to the individual which affect that person’s susceptibility to the effects of heavy drinking and risk for developing dependence, as well as factors that contribute to treatment efficacy.

Implicit memory tests assess, for example, improved performance on a motor skill or ability to select a word infrequently used to complete a word stem (e.g., when asked to complete “STR _ _ _,” answer “STRAIT” instead of the more commonly used “STREET”). Alcoholic KS patients show notable impairment on tests of explicit memory, especially those requiring open-ended recall without cues, but are relatively spared on verbal (i.e., word stem completion [Verfaellie and Keane 2002]) and non-verbal (i.e., picture completion [Fama et al. 2006]) tests of implicit memory. That cueing can enhance remembering of new explicitly learned information by KS patients suggested that retrieval processes are more affected than encoding or consolidation processes. Over time, excessive drinking can lead to mental health problems, such as depression and anxiety. Alcohol abuse can increase your risk for some cancers as well as severe, and potentially permanent, brain damage.

Teenagers are likely to engage in high-risk behaviors, such as driving under the influence and using other substances. Alcohol lowers inhibitions and clouds judgment, which may lead you to engage in risky behaviors. Research has shown that alcohol can exacerbate symptoms and mood changes in people with mental health disorders like depression or bipolar disorder.

Scar tissue impairs the liver’s ability to create proteins, filter the blood, and other bodily functions. Conversely, other recent data suggest a lower risk for dementia in people consuming a few alcoholic beverages drug addiction blog a day. This includes a 2022 study showing that in around 27,000 people, consuming up to 40 grams of alcohol (around 2.5 drinks) a day was linked to a lower risk for dementia versus abstinence in adults over age 60.

Brain imaging technology has allowed researchers to conduct rigorous studies of the dynamic course of alcoholism through periods of drinking, sobriety, and relapse and to gain insights into the effects of chronic alcoholism on the human brain. Magnetic resonance imaging (MRI) studies have distinguished alcohol-related brain effects that are permanent from those that are reversible with abstinence. In support of postmortem neuropathological studies showing degeneration of white matter, MRI studies have shown a specific vulnerability of white matter to chronic alcohol exposure. Such studies have demonstrated white-matter volume deficits as well as damage to selective gray-matter structures.

An MRI image of acute WE (see figure 2) has symmetrical bright spots, or hyperintensities, clearly visible on T2-weighted images, and those created by fluid attenuation inversion recovery2 (FLAIR). The bright spots appear in the midbrain gray matter surrounding the cerebral aqueduct (i.e., periaqueductal gray matter), mammillary bodies, and tissue surrounding the third ventricle3 (Lenz et al. 2002; Sullivan and Pfefferbaum 2009). These findings agree with postmortem diagnosis of WE, often requiring evidence of lesions in the mammillary bodies and periventricular areas (e.g., Caine et al. 1997). In addition, observed MR hyperintense areas in WE include the thalamus, cerebellar vermis (Murata et al. 2001), dorsal medulla, tectal plates (Ha et al. 2012), olivary bodies, and dorsal pons (Liou et al. 2012). In contrast with early MR studies suggesting that KS affects the mammillary bodies while sparing the hippocampi (Squire et al. 1990), more recent work demonstrates hippocampal volume deficits in KS (Sullivan and Marsh 2003).

Advances in neuroscience continue to shed light onto regulatory mechanisms relevant for alcohol use. A striking example is the discovery that certain neurotransmitters, such as serotonin [109] and dopamine [110], can covalently bind to histones and act as epigenetic marks to regulate gene expression. Histone do you genuinely like the feeling of being drunk dopaminylation was further shown to influence addiction-like behaviors in the context of cocaine exposure in mice [110]. This novel mechanism could have far reaching implications for other drugs of abuse, including alcohol, which are known to increase dopamine levels in the mesolimbic system [72].

A 36% reduction in Purkinje cell numbers in the flocculi suggests disruption of vestibulocerebellar pathways. This is of particular interest given recent data showing the importance of cerebellum in the organization of higher order cerebral functions (Schmahmann 2000). Myo-inositiol is present in glial but not neuronal cell cultures (Brand et al. 1993; Petroff et al. 1995) and plays a role in maintaining cell volume (Ernst et al. 1997; Lien et al. 1990). The concentration of mI is higher in gray than in white matter (Michaelis et al. 1993; Pouwels and Frahm 1998). One of the more desirable approaches is the use of quantitative fiber tracking, which is able to evaluate fibers along their entire length and can thus detect compromised white matter.

Cortisol, in turn, increases mesencephalic dopaminergic transmission that underlies the activation of alcohol-induced brain reward circuitry (Bowirrat and Oscar-Berman 2005; Gianoulakis 1998; Piazza et al. 1996), in which the amygdala plays an essential role (Koob 2003). These additional abnormalities reflect widespread cerebral atrophy accompanying sustained alcohol abuse. Thus, consideration should be given to sensory and cognitive deficits that may be integral to the disease process caused by chronic alcoholism. Results of neurobehavioral investigations tend to support the view that aging increases one’s vulnerability to alcoholism-related decline (Oscar-Berman and Marinkovic 2003).

These analyses found that a change in processing strategy occurs, where alcoholics use inefficient neural systems to complete a task at hand because the preferred neural nodes or connecting fiber tracks are compromised. Such compensatory activation may be crucial for adequately completing a task but curtails available capacity to carry out multiple activities in parallel. Ultimately, structural abnormalities impose a fundamental change in the choice of cognitive operations possible for the alcoholic (see figure 5). In this way, alcohol-induced insult to the brain that limits higher-order cognitive capacity may sustain the propensity to engage in harmful drinking and enable the alcohol dependence syndrome. These compensatory brain mechanisms identified with fMRI are consistent with earlier theories about processing inefficiency based on cognitive testing only (Nixon et al. 1995; Ryback 1971). Dopaminergic function following chronic alcohol consumption has been extensively investigated with several targets for potential therapeutics being discovered.

The good news is that within a year of stopping drinking, most cognitive damage can be reversed or improved. Ethanol is classified as a “depressant” because it has a generally slowing effect on brain activity through activation of γ-aminobutyric acid (GABA) pathways. Consumption of alcohol has and continues to serve major roles in religious and cultural ceremonies around the world. But unlike most food products, in the last century, alcohol has been wrapped up in nearly perpetual controversy over its moral effects and health implications.

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