Addiction to and problematic use of the Internet are relatively recent phenomena whose scope, characteristics and correlates have begun to receive increasing attention by clinicians and researchers alike. The purpose of this study was to examine the relationship between time spent connected to the Internet and the variables that indicate a pathological and addictive use of this technological resource. The sample was comprised of 1,301 university students of both sexes (927 women and 374 men), with ages ranging from 18 to 30 years old. The results showed that, although most people use the Internet appropriately, users who invest higher quantities of time in the Internet more frequently exhibit connection behavior that is controlled through negative reinforcement, a high degree of arousal when online, loss of control over connection behavior, changes in health-related habits, and interference in the social, family, academic, or work spheres. These findings suggest that excessive Internet use is associated with the onset of several problems that are similar to those associated with other behavioral and technological addictions.

The goal of this study is to examine the relationship between substance use (i.e., alcohol and illegal drugs) and dating aggression in couples of adolescents and young adults. The sample comprised 1,282 people of between 15 and 20 years of age. Through cluster analysis, three groups of young people with different levels of substance use were identified: low, intermediate, and high use of alcohol and illegal drugs. Through logistic regression analysis, high levels of alcohol and illegal drug use were revealed to significantly increase the probability of reporting physical and sexual aggression in both sexes. Likewise, young people with high levels of use more frequently reported that they were the ones who initiated episodes of aggression against their partners. The results suggest that alcohol and drug use is a risk factor for dating aggression, a finding that should be taken into account for the prevention of intimate partner violence, beginning in adolescence.Key words: dating aggression, alcohol use, illegal drugs, sexual aggression, adolescence, risk behaviors. RESUMEN ABSTRACTEl objetivo de este estudio fue examinar la relación entre consumo de sustancias (i.e., alcohol y drogas ilegales) y violencia en parejas de adolescentes y jóvenes. La muestra estuvo compuesta por 1.282 participantes entre 15 y 20 años. A través de análisis de conglomerados se identificaron tres grupos de adolescentes y jóvenes con diferentes niveles de consumo de sustancias: bajo, moderado y elevado consumo de alcohol y drogas ilegales. Se efectuaron varios análisis de regresión logística para pronosticar cada tipo de agresión contra la pareja (física, psicológica y sexual) a partir del nivel de uso de sustancias. Niveles elevados de consumo de alcohol y drogas ilegales incrementaron significativamente la probabilidad de informar de agresión física y sexual para ambos sexos.Asi mismo, los participantes con un nivel elevado de consumo informaron con mayor frecuencia que eran ellos quienes iniciaban los episodios de agresión contra su pareja. Los resultados sugieren que el uso de alcohol y drogas constituye un factor de riesgo para la violencia en el noviazgo, hecho que ha de ser tenido en cuenta para la prevención de la violencia en la pareja ya desde la adolescencia.