Hypothalamic syndrome.

Hypothalamic syndrome (HS) is a rare disorder caused by disease-related and/or treatment-related injury to the hypothalamus, most commonly associated with rare, non-cancerous parasellar masses, such as craniopharyngiomas, germ cell tumours, gliomas, cysts of Rathke's pouch and Langerhans cell histiocytosis, as well as with genetic neurodevelopmental syndromes, such as Prader-Willi syndrome and septo-optic dysplasia. HS is characterized by intractable weight gain associated with severe morbid obesity, multiple endocrine abnormalities and memory impairment, attention deficit and reduced impulse control as well as increased risk of cardiovascular and metabolic disorders. Currently, there is no cure for this condition but treatments for general obesity are often used in patients with HS, including surgery, medication and counselling. However, these are mostly ineffective and no medications that are specifically approved for the treatment of HS are available. Specific challenges in HS are because the syndrome represents an adverse effect of different diseases, and that diagnostic criteria, aetiology, pathogenesis and management of HS are not completely defined.

Automated diffusion-based parcellation of the hypothalamus reveals subunit-specific associations with obesity.

The hypothalamus is a small, yet highly versatile structure mainly involved in bodily functions such as control of food intake and endocrine activity. Functional anatomy of different hypothalamic areas is mainly investigated using structural MRI, validated by ex-vivo histological studies. Based on diffusion-weighted imaging (DWI), recent automated clustering methods provide robust tools for parcellation. Using data of 100 healthy adults provided by the Human Connectome Project Database, we applied DWI-based automated clustering to the hypothalamus and related microstructural properties in these hypothalamic compartments to obesity. Our results suggest that the hypothalamus can be reliably partitioned into four clusters in each hemisphere using diffusion-based parcellation. These correspond to an anterior-superior, anterior-inferior, intermediate, and posterior cluster. Obesity was predicted by mean diffusivity of the anterior-superior cluster, suggesting altered inhibition of food intake. The proposed method provides an automated hypothalamic parcellation technique based on DWI data to explore anatomy and function of hypothalamic subunits in vivo in humans.

Eating behaviour and oxytocin in patients with childhood-onset craniopharyngioma and different grades of hypothalamic involvement.

BACKGROUND: Patients with childhood-onset craniopharyngioma (CP) often suffer from tumour or treatment-related hypothalamic lesions (HL). These lesions may alter production of oxytocin, which plays a major role in the regulation of eating behaviour and body composition. OBJECTIVE: In CP with different degrees of HL, we investigated associations between HL, eating behaviour/eating attitudes, and oxytocin saliva concentrations (OSC). METHODS: In a cross-sectional case-control study on 34 CP and 73 healthy controls, OSC were measured before, and 60 minutes after breakfast by immunoassay. Eating behaviour, attitudes, and habits were assessed by standardized questionnaires. RESULTS: CP with anterior + posterior HL presented with more adverse eating behaviours/symptoms of eating disorders than CP without HL, CP with anterior HL, and controls. Eating behaviour in CP with anterior HL was similar to controls, except for their tendency towards high dietary restraints. Decreases in postprandial compared with fasting OSC were associated with adverse eating behaviour in CP and controls and with higher BMI in CP. CONCLUSIONS: CP with anterior HL and CP with anterior + posterior HL present with distinct patterns of eating behaviour. Reduced postprandial compared with fasting OSC is associated with weight problems in CP and with adverse eating behaviour and symptoms of eating disorders in both CP and controls.

Effects of mindfulness and psychoeducation on working memory in adult ADHD: A randomised, controlled fMRI study.

Adult attention-deficit/hyperactivity disorder (ADHD) is a serious mental disorder associated with impaired neurocognitive performance related to working memory function. Recent clinical trials have suggested that mindfulness is a promising intervention in adults with ADHD. We performed a randomised controlled clinical trial to investigate working memory (WM) with an n-back task in adults with ADHD during fMRI before and after an 8-week mindfulness intervention (MAP) compared with psychoeducation (PE). ADHD symptoms were assessed using the self- and observer-rated Conners Adult ADHD Rating Scales (CAARS). The complete pre-post data of 21 MAP and 19 PE participants were analysed. We found no group difference in ADHD symptoms or task performance at the pre-measurement, but there was a significant decrease in ADHD symptoms and significant improvement in task performance in both groups at the post-measurement. Furthermore, we found a significant increase in task-related activation in the right parietal lobe, with no difference between groups. Exploratory two-sample paired t-tests revealed significant increased brain activation after MAP in the bilateral inferior parietal lobule, right posterior insula and right precuneus. A decrease in self-rated 'Inattention/Memory Problems' after MAP compared to baseline was associated with stronger activation in parts of the left putamen, globus pallidus and thalamus.

Remote effects of hypothalamic lesions in the prefrontal cortex of craniopharygioma patients.

Albeit histologically low grade (WHO I(o)) brain tumors, craniopharyngiomas and/or their surgical removal frequently affect the hypothalamus, amongst other brain regions at risk. Due to rich hypothalamic connections with prefrontal and limbic regions, hypothalamic injury may adversely affect neural substrates of emotion processing and higher cognitive control, including memory and executive functions. The current study is the first to investigate the consequences of hypothalamic involvement on neural substrates of emotional and cognitive functioning. Ten patients with childhood craniopharyngioma and known hypothalamic involvement and fifteen age- and intelligence matched control subjects (median age: 17.8 and 17.3 yrs.) were studied with functional magnetic resonance imaging and an emotional face recognition task. During encoding, participants were asked to classify neutral and emotional faces. In a subsequent recognition phase, participants had to recognize these old faces within a set of new faces. Behavioral performance was comparable between patients and controls. Neural activity revealed, however, differential recruitment of fronto-limbic brain regions during recognition. Patients exhibited an abnormal pattern of task-induced activation and deactivation in the anterior and posterior rostral medial prefrontal cortex and a higher functional coupling between anterior rostral medial prefrontal cortex and the thalamus. Additionally, we found a higher reactivity in the patients' amygdala to emotional relative to neutral faces when compared to healthy controls. Our data provide first evidence that hypothalamic damage impacts neural correlates of memory retrieval in medial prefrontal cortex, indicating a less efficient use of an area involved in executive control processes. We propose that the deactivation failure in the patients' anterior rostral medial prefrontal cortex is related to an increased coupling with the thalamus and reflects a reduced efficiency to flexibly adapt to task demands.

Pitch-induced responses in the right auditory cortex correlate with musical ability in normal listeners.

Previous work compellingly shows the existence of functional and structural differences in human auditory cortex related to superior musical abilities observed in professional musicians. In this study, we investigated the relationship between musical abilities and auditory cortex activity in normal listeners who had not received a professional musical education. We used functional MRI to measure auditory cortex responses related to auditory stimulation per se and the processing of pitch and pitch changes, which represents a prerequisite for the perception of musical sequences. Pitch-evoked responses in the right lateral portion of Heschl's gyrus were correlated positively with the listeners' musical abilities, which were assessed using a musical aptitude test. In contrast, no significant relationship was found for noise stimuli, lacking any musical information, and for responses induced by pitch changes. Our results suggest that superior musical abilities in normal listeners are reflected by enhanced neural encoding of pitch information in the auditory system.