Out of the three PET studies summarized in Table 2, two studies not match groups on age [111,112] and two did not find significant differences between groups on cognitive measures [110,111]. The clinical importance of both Bolla et al. [111] and Goldstein et al. [112] remains ambiguous. Both studies found that cocaine abusers exhibited a degree of cognitive impairment. While Bolla et al. [111] based their conclusions on PET findings, those of Goldstein et al. [112] were derived from a neuropsychological test battery. The studies also differed in sample size, number of tasks administered, and use or non-use of demographically adjusted scores. It is unclear what PET imaging tells us about the neurocognitive functioning of individuals with cocaine use disorder, given that findings are open to debate and that doubts persist as to whether metabolic changes in the brain are linked to a specific drug of abuse.
I interpret the authors as saying that it’s unclear whether there’s any difference at all, much less a “pretty bad” one.
Here’s a longer quote from the article:
I interpret the authors as saying that it’s unclear whether there’s any difference at all, much less a “pretty bad” one.