Category specific semantic impairments - give some examples. How can these impairments be explained?

Category specific semantic impairments - give some examples. How can these impairments be explained?

Patient EW, was impaired in terms of animate living things, picture naming, object decision, sound identification and central attribute judgements. In general specific impairments can be explained because our knowledge processing is distributed over many brain areas, with each one having a/several specific functions. If damage occurs to any of these areas than the abilities associated with that particular area may be lost.

An example from our textbook is an Italian woman who suffered from encephalitis at age of 44, when she returned home after hospitalization, she was unable to recognize familiar people, had trouble shopping (she couldn't remember the meaning of the words on the shopping list), couldn't recognize famous people or even recall some historical facts. Although her semantic memory was severely impaired she was still able to form new episodic memories. These impairments can be explained as Tim said. What's interesting though is that many people who suffer from impairment of semantic memory had herpes simplex encephalitis.