Neuroanatomy and Neuropathology Associated with Korsakoff’s Syndrome

Abstract

Although the neuropathology of Korsakoff’s syndrome (KS) was first described well over a century ago and the characteristic brain pathology does not pose a diagnostic challenge to pathologists, there is still controversy over the neuroanatomical substrate of the distinctive memory impairment in these patients. Cohort studies of KS suggest a central role for the mammillary bodies and mediodorsal thalamus, and quantitative studies suggest additional damage to the anterior thalamus is required. Rare cases of KS caused by pathologies other than those of nutritional origin provide support for the role of the anterior thalamus and mammillary bodies. Taken together the evidence to date shows that damage to the thalamus and hypothalamus is required, in particular the anterior thalamic nucleus and the medial mammillary nucleus of the hypothalamus. As these nuclei form part of wider memory circuits, damage to the inter-connecting white matter tracts can also result in a similar deficit as direct damage to the nuclei. Although these nuclei and their connections appear to be the primary site of damage, input from other brain regions within the circuits, such as the frontal cortex and hippocampus, or more distant regions, including the cerebellum and amygdala, may have a modulatory role on memory function. Further studies to confirm the precise site(s) and extend of brain damage necessary for the memory impairment of KS are required.

Neurocognitive, psychosocial and functional status of individuals with alcohol-related brain damage (ARBD) on admission to specialist residential care

“…Therefore, the findings also provide evidence for executive dysfunction in ARBD, which is in line with recent postulations that ARBD is not solely associated with anterograde amnesia (Van Oort and Kessels, 2009;Maharasingam et al, 2013;Brion et al, 2014). The neurocognitive profile observed in this study reflects current knowledge about the structural brain abnormalities that are associated with ARBD, including damage to the brain regions underpinning memory, such as the mammillary bodies, anterior thalamus, mammilothalamic tract and hippocampus, as well as damage to the prefrontal brain circuitry involved in executive functions such as behavioural inhibition (Kril & Harper, 2012;Oscar-Berman, 2012;Zahr, Kaufman & Harper, 2011).…”

Comparing neurostimulation technologies in refractory focal-onset epilepsy

“…Neuropathological studies indicate that involvement of the medial mammillary nucleus and the ANT is required for the episodic memory deficit that characterises the Korsakoff syndrome 33. Patients with vascular thalamic amnesia also have prominent deficits in declarative anterograde memory, with less consistent deficits in retrograde declarative memory.…”

Anterior nucleus of the thalamus

“…35 Neuropathologic studies indicate that involvement of the medial mammillary nucleus and the ANT is required for the episodic memory deficit that characterizes Korsakoff syndrome, although the dorsomedial nucleus of the thalamus is also frequently involved. 36 Patients with vascular thalamic amnesia also have prominent deficit in declarative anterograde memory, with less consistent deficit in retrograde declarative memory. Involvement of the mammillothalamic tract connecting the ANT to the hippocampus bodies strongly predicts the presence of this amnestic syndrome in patients with thalamic lacunar infarcts.…”