Biological processes are the physical and chemical processes that occur within living organisms. These processes include metabolism, respiration, cell division, growth, and reproduction. Psychological phenomena are the conscious and unconscious experiences that occur within an individual. These experiences include thoughts, emotions, behaviors, and sensations.
The relationship between biological processes and psychological phenomena is complex. Biological processes can influence psychological phenomena, and vice versa. For example, hormones can affect mood and behavior. Brain injuries can cause changes in cognition and personality. And mental illnesses can alter brain structure and function.