Narkolepsi

Brain Networks and Dynamics in Narcolepsy

Narcolepsy is a chronic sleep disorder, characterised by excessive daytime sleepiness with frequent uncontrollable sleep attacks. In addition to sleeprelated problems, changes in cognition have also been observed in patients with narcolepsy and has been linked to the loss of Orexin-A in a number of studies. Results from previous functional and structural neuroimaging studies would suggest that the loss of Orexin-A has numerous downstream effects in terms of both resting state glucose metabolism and perfusion and reduction in cortical grey matter. Specifically, studies investigating narcolepsy with positron emission tomography (PET) and single photon emission computed tomography (SPECT) have observed aberrant perfusion and glucose metabolism in the hypothalamus and thalamus, as well as in prefrontal cortex. A very recent PET study in a large cohort of adolescents with type 1 narcolepsy further observed that the hypoand hypermetabolism in many of these cortico-frontal and subcortical brain regions also exhibited significant correlations with performance on a number of neurocognitive tests. These findings parallel those found in structural neuroimaging studies, where a reduction of cortical grey matter in frontotemporal areas has been observed. The Aim of this thesis was to investigate mechanisms and aetiology behind the symptoms in narcolepsy through the application of different neuroimaging techniques. I present in this thesis evidence supporting that the complaints about subjective memory deficits in narcolepsy are related to a misallocation of resources. I further describe how this has its seat in defective default mode network activation, possibly involving alterations to GABA and Glutamate signaling. In addition to this, I present our findings of a structural deviation in an area of the brainstem previously not described in the aetiology of narcolepsy. This finding may have implications for further understanding the aetiology of the disease and the specific neuronal populations involved. In addition to this, I show evidence from adipose tissue measurements in specific compartments, confirming that weight gain in narcolepsy is characterized by centrally located weight gain and may be specifically related to OX changes, but maybe not brown adipose tissue volume. The findings presented in this thesis provides new insights to the pathophysiology of narcolepsy beyond the well-known depletion of OX producing neurons in the hypothalamus.

Ayo Bangun

Psikologi Umum Lanjutan

Psikologi adalah salah satu bidang yang menarik perhatian banyak orang. Tema-tema yang dipelajari dalam psikologi sebenarnya merupakan tema-tema yang sering (bahkan selalu) kita temui dalam kehidupan sehari-hari. Misalkan, tes psikologi dalam seleksi penerimaan karyawan, perasaan traumatik akibat peristiwa masa lalu, kehilangan motivasi, proses berpikir, pola asuh, tingkatan kesadaran, mimpi, konsep diri, bakat, minat, dan kecerdasan. Tema lain yang tak kalah menarik adalah tentang gangguan kejiwaan. Berbagai tema tersebut masih banyak dipahami secara kurang tepat dan kurang proporsional sehingga menyebabkan respons perilaku yang juga kurang tepat. Terutama, tema tentang gangguan kejiwaan yang memunculkan respons intimidatif akibat pola berpikir yang kurang komprehensif. Buku Psikologi Umum Lanjutan ini pada dasarnya adalah lanjutan dari buku penulis sebelumnya berjudul Psikologi Umum Dasar yang terbit tahun 2022. Dalam buku Psikologi Umum Lanjutan ini penulis membahas beberapa tema yang lebih luas dan mendalam, seperti tentang berbagai tingkatan kesadaran dan kajian seputar kesadaran (mimpi, hipnosis, dan meditasi serta zat-zat psikoaktif); atensi, sensasi, dan persepsi; proses belajar dan mengingat (model-model pembelajaran, jenis ingatan, serta cara meningkatkan ingatan); proses belajar; proses mengingat; motivasi dan teori motivasi; kognisi sosial, perilaku sosial, dan hubungan; sikap dan prasangka; perasaan dan emosi; serta bakat dan minat. Pembahasan di dalam buku ini diharapkan dapat membantu masyarakat untuk memahami tema-tema psikologi secara mendalam, tepat, kontekstual, dan proporsional. Selamat membaca. Buku persembahan penerbit PrenadaMediaGroup #Kencana