Current approaches for the processing and analysis of EEG signals consist mainly of three phases: preprocessing, feature extraction, and classification. The analysis of EEG signals is through different domains: time, frequency, or time-frequency; the former is the most common, while the latter shows competitive results, implementing different techniques with several advantages in analysis. This paper aims to present a general description of works and methodologies of EEG signal analysis in time-frequency, using Short Time Fourier Transform (STFT) as a representation or a spectrogram to analyze EEG signals.