Gregor's journey through The Metamorphosis is marked by a shrinking sense of self and identity due to the belittlement and violence inflicted upon him by family & acquaintances. This shrinking is represented not only internally through feelings of inferiority, but also physically in his character through imagery of confinement, starvation and debilitation. .
Almost immediately after revealing his transformed–self to his family, his mother responds with absolute terror and his father attacks him and locks him away in his room,.
"Gregor drove himself – happen what might – against the door. One side of his body was canted up, he found himself lifted at an angle in the doorway, his flank was rubbed raw from behind his father now gave him a truly liberating kick, and he was thrown, bleeding profusely, far into his room. The door was battered shut and then at last there was quiet." (Kafka 106).
Imagery of physical shrinking is apparent in this piece of text. Gregor is too wide to fit into the doorway of his bedroom, so his father shoves and kicks him in, scraping off part of the side of his body and actually making him physically smaller by force. What's interesting is that Gregor describes this clearly painful altercation as "truly liberating". This could be interpreted as sarcasm, but it's more likely that his father's kick truly is liberating for him; now he is safe – albeit injured – in his room. Gregor the cockroach –contrary to Gregor the human– craves solitude over the battery and physical abuse of his family. This is the first piece of Gregor to be lost in his transformation: his relationships with the people around him. Physical shrinking appears again when the door is "battered shut" and Gregor is confined to his bedroom. This confinement physically shrinks the available space around him, although he now finds solace in his prison-like space.