The conceptual framework of the attachment theory (the bonds that are formed early in life with parental figures derive from the need to feel safe and secure) and of human information processing (the process used to filter out or let through unwanted information) have been combined to explain loss and bereavement.[1-4]

The bereavement process can be divided into four phases:

1. Shock and Numbness: During this initial phase, survivors have difficulty processing the information of the loss; they are stunned and numb.
2. Yearning and Searching: In this phase, there is a combination of intense separation anxiety and disregard or denial of the reality of the loss. This engenders a desire to search for and recover the lost person. Failure of this search leads to repeated frustration and disappointment.
3. Disorganization and Despair: In this phase, individuals often report being depressed and have difficulty planning future activities. These individuals are easily distracted and have difficulty concentrating and focusing.
4. Reorganization: This phase overlaps somewhat with the third phase.

The phases modulate to allow existing internalized, representational figures of safety and security to be reshaped, incorporating the changes that have occurred in the life of the bereaved.

References

1. Bowlby J: Processes of mourning. Int J Psychoanal 42: 317-40, 1961. 
   
   
2. Bowlby J: Attachment and Loss. vols. 1-3, New York: Basic Books, Inc., 1969-1980. 
   
   
3. Parkes CM: Bereavement: Studies of Grief in Adult Life. 2nd ed., Madison: International Universities Press Inc., 1987. 
   
   
4. Parkes CM: Bereavement as a psychosocial transition: processes of adaptation to change. J Soc Issues 44 (3): 53-65, 1988.