LA MESA, Calif. (FOX 5/KUSI) -- The search continues for a 71-year-old woman with dementia who has been missing for four weeks, authorities said. Vivian Crowder was last seen on Tuesday, Oct. 29, walking along the right shoulder of northbound 125 near the Interstate 8 overpass, Katy Lynch with the La Mesa Police Department said in a news release Tuesday. First responders received a report of the sighting around 12:14 p.m. When they arrived on scene, they did not find her. "We are hoping that a good Samaritan picked her up and drove her someplace, and if so, we hope they will contact us and let us know where they took her," Lynch said. Crowder is described as 160 pounds and 5 feet 2 inches. She is familiar with the trolley and bus system but does not know the East County area, according to police. Vivian Crowder has been missing since Oct. 29. (La Mesa Police Department) Authorities say Crowder, who is friendly and would talk to anyone, appeared very confused on the day she went missing. Anyone with information can call the law enforcement's tip line at 619-667-7537, or they may call 911 if they believe they have seen her.