The final groups of marihuana users are the moderate and heavy users. This range is wide and includes individuals who use marihuana more than 10 times a month to several times a day. Practically all of the American research effort to date has focused on the large majority of individuals who use less often, that is, the experimental and intermittent users. Consequently, not enough is known about characteristics and behavior of the moderate and the heavy users, so it is difficult to distinguish accurately between the two groups. We suspect however that the moderate users share traits with both the intermittent and the heavy users. Having already discussed the intermittent group, we will now turn to the characteristics of the heavy group.

Heavy users seem to need the drug experience more often. Their initial and continued marihuana use is motivated not only by curiosity and an urge to share a social experience but also by a desire for "kicks," "expansion of awareness and understanding," and relief of anxiety or boredom.

Generally, the heavy marihuana user's life style, activities, values and attitudes are unconventional and at variance with those of the, larger society. These individuals are more pessimistic, insecure, irresponsible, and nonconforming. They find routine especially distasteful. Their behavior and mood are restless and uneven.

Heavy users place particularly strong emphasis on impulsive response in the interest of pleasure-seeking, immediate gratification, and individual expression. They tend to evidence social and emotional immaturity, are especially indifferent to rules and conventions, and are often resistant to authority. However, several surveys have also revealed that they tend to be curious, socially perceptive, skillful and sensitive to the needs of others, and possess broadly based, although unconventional, interests.

The Boston free-access study permitted the Commission to observe a group of individuals whose life styles, activities, values and attitudes are representative of a segment of the unconventional youthful subculture. The month-long period of controlled study during the fall prevented the participation of individuals who were married, steadily employed, or enrolled in school.

Individuals who smoked marihuana once a week or less were sought by the researchers but were exceedingly unusual among the population available for the study. Consequently, the group studies contrasted with the student and full-time working populations in which weekly marihuana use is more common. For this reason, the intermittent users studied appeared to be similar to, rather than different from, the moderate and heavy users studied. Both groups had used marihuana for an average of five years.

Under the study's confined conditions, participants tended to smoke more marihuana than they did "on the outside." The intermittent users, who by our definition averaged eight times a month under outside conditions, averaged three cigarettes a day during the study. The range was from one-half to six cigarettes daily.

The moderate and heavy users, who "on the outside" averaged 33 times a month, now averaged six-and-a-half cigarettes a day. The range was three-and-a-half to eight cigarettes. In discussing the Boston study, we will call this group "daily" users.

Smoking usually occurred at night, sometimes during the afternoon and only occasionally upon awakening. The intermittent and heavy users usually smoked one cigarette a session. The daily users were more likely to smoke more than one a session. A few individuals in the daily group could have been considered constantly intoxicated on a few occasions during the 21 -day period.

The mean age of the subjects studied was 23. Based on IQ testing, they were superior intellectually, although they had completed, on the average, only two-and-a-half years of college. Their job histories were rather erratic, characteristic of a pattern of itinerant living. The intermittent users -were from a middle or upper class background, while the daily users generally shared a lower socioeconomic status. Broken homes and instances of alcohol or drug abuse were more common in the family backgrounds of the daily users.

Alcohol was rarely used by the subjects. Use of hallucinogens and amphetamines was significantly more widespread and had begun earlier in the daily user group. In contrast to the intermittent group, the daily users almost uniformly reported that marihuana smoking produced relaxation, noting also increased alteration in perception or psychedelic-like effects. Similarly, they reported an increased sense of well-being, friendliness, carefreeness and decreased hostility. Additionally, the daily users appeared to demonstrate a moderate psychological dependence on the marihuana experience while the intermittent users demonstrated little or no psychological dependence.

Analysis of social-behavioral aspects of daily users' marihuana smoking clearly demonstrated that it is a pivotal social activity around which conversation, other personal interactions, and much of the users' lives revolve. Smoking almost exclusively occurred in groups and was the focal activity around which these groups formed. The daily users exhibited a readiness to take part in but not to initiate a smoking session.

In contrast to the intermittent users, all the daily users in a group smoked when marihuana was made available. Marihuana smoking appeared to be a primary means of reinforcing group solidarity. Yet these users were more inclined to seek the personal effects of the drug rather than the socializing effects sought by the intermittent users.

The social adjustment of the daily users, when judged from a traditional psychiatric standpoint, was impaired. Individuals tended to be more withdrawn and to interact less with each other than the intermittent users, regardless of the type of activity or state of intoxication. However, the daily users did appear to accommodate themselves better than the intermittent users to the effects of the intoxication on social interaction.

Despite a relatively high level of scholastic attainment and superior intelligence, many of the subjects were performing well below their intellectual capability, usually working at menial, mechanical or artisan tasks. They were not oriented toward achieving the traditional goals of the larger society.

Nonetheless, during the period of the Boston study, the subjects could not be characterized as displaying a general lassitude and indifference, carelessness in personal hygiene or lack of productive activity, all supposed to be characteristic of very heavy use. Even during the periods of heaviest marihuana smoking, they maintained a high level of interest and participation in a variety of personal activities, such as writing, reading, keeping up on current world events, and participating in athletic and aesthetic endeavors.

Additionally, all of the subjects maintained a desire to complete all aspects of the research study. Although they could be labeled 'underachievers" in terms of the traditional standards of the larger society, these individuals were motivated to pursue actively the interests and activities of their own subculture.

Generally, most studies which have been undertaken indicate that individuals who are heavy marihuana users cannot find a place for themselves in conventional society. Their heavy marihuana use may reflect and perhaps perpetuate their unconventionality while providing social acceptance in one of the non-conventional subcultures.