В Вибханга сутте объясняется происхождение ощущений телесной и психической природы:
Pañcimāni, bhikkhave, indriyāni. Katamāni pañca? Sukhindriyaṃ, dukkhindriyaṃ, somanassindriyaṃ, domanassindriyaṃ, upekkhindriyaṃ.
"Monks, there are these five faculties. Which five? The pleasure-faculty, the pain-faculty, the happiness-faculty, the distress-faculty, the equanimity-faculty.
Katamañca bhikkhave, sukhindriyaṃ: yaṃ kho bhikkhave, kāyikaṃ sukhaṃ, kāyikaṃ sātaṃ kāyasamphassajaṃ sukhaṃ sātaṃ vedayitaṃ, idaṃ vuccati bhikkhave, sukhindriyaṃ.
"And what is the pleasure-faculty? Any physical pleasure, physical comfort born of body-contact to be experienced as pleasure & comfort. That is called the pleasure-faculty.
Katamañca bhikkhave, dukkhindriyaṃ: yaṃ kho bhikkhave, kāyikaṃ dukkhaṃ, kāyikaṃ asātaṃ kāyasamphassajaṃ sukhaṃ asātaṃ vedayitaṃ, idaṃ vuccati bhikkhave, dukkhindriyaṃ.
"And what is the pain-faculty? Any physical pain, physical discomfort born of body-contact to be experienced as pain & discomfort. That is called the pain-faculty.
Katamañca bhikkhave, somanassindriyaṃ: yaṃ kho bhikkhave, cetasikaṃ sukhaṃ, cetasikaṃ sātaṃ manosamphassajaṃ sukhaṃ sātaṃ vedayitaṃ, idaṃ vuccati bhikkhave, somanassindriyaṃ.
"And what is the happiness-faculty? Any mental pleasure, mental comfort born of intellect-contact to be experienced as pleasure & comfort. That is called the happiness-faculty.
Katamañca bhikkhave, domanassindriyaṃ: yaṃ kho bhikkhave, cetasikaṃ dukkhaṃ, cetasikaṃ asātaṃ manosamphassajaṃ dukkhaṃ asātaṃ vedayitaṃ, idaṃ vuccati bhikkhave, domanassindriyaṃ.
"And what is the distress-faculty? Any mental pain, mental discomfort born of intellect-contact to be experienced as pain & discomfort. That is called the distress-faculty.
Katamañca bhikkhave, upekkhindriyaṃ: yaṃ kho bhikkhave, kāyikaṃ vā cetasikaṃ vā neva sātaṃ nāsitaṃ vedayitaṃ, idaṃ vuccati bhikkhave, upekkhindriyaṃ.
"And what is the equanimity-faculty? Anything, physical or mental, to be experienced as neither comfort nor discomfort. That is called the equanimity-faculty.
Tatra bhikkhave yañca sukhindriyaṃ yañca somanassindriyaṃ sukhā sā vedanā daṭṭhabbā. Yañca dukkhindriyaṃ yañca domanassindriyaṃ tatra bhikkhave, dukkhā sā vedanā daṭṭhabbā. Tatra bhikkhave, yamidaṃ upekkhindriyaṃ adukkhamasukhā sā vedanā daṭṭhabbā. Imāni kho bhikkhave, imāni pañcindriyāni pañca hutvā tīni honiti. Tīni hutvā pañca honti pariyāyenāti.
"With regard to this, the pleasure-faculty & happiness-faculty are to be seen as a feeling of pleasure. The pain-faculty & distress-faculty are to be seen as a feeling of pain. The equanimity-faculty is to be seen as a feeling of neither pleasure nor pain. Thus, by this exposition, the five are three; and the three, five."
http://www.accesstoinsight.org/tipitaka/sn/sn48/sn48.038.than.html