Hot cognition is a component of executive functions which are cognitive functions like reasoning, attention, problem solving, organizing, planning, and timing. Executive functions manage and regulate mental processes.
Two opposing components of executive functions are hot and cold cognition.
Hot cognition are executive functions that are influenced by emotion. Arousal (both mental and physical stimulation) occurs when emotions influence behavior and this affects our cognition. It involves cognitive processes that are influenced by arousal and current emotions. Hot cognition is very fast and is frequently biased and may not be the appropriate reaction. It is an automatic process that is mostly influenced by emotion.
The other side of the executive function spectrum is cold cognition. it can be described as cognitive functions and thinking that are logical and based on reason. Emotions are not as influential in cold cognition as they are in hot cognition.
An example of hot cognition would be immediately disliking and being rude to your friend's ex when meeting them for the first time. The person may actually be a very nice person but the judgment and behaviors are inappropriate because they are influenced by emotion.