Browse every published article, from the latest research to earlier analysis. Use the page numbers below to explore the complete archive.
Mice lacking the TAAR1 receptor showed stronger methamphetamine-related behavioral responses, while a morphine comparison did not show the same genotype pattern. That comparison helps define the finding as a drug-specific experimental result rather than a universal increase in reward behavior. Two behavioral questions Achat-Mendes and colleagues compared wild-type mice with transgenic mice lacking trace amine-associated…
A small modafinil pilot found reduced self-reported methamphetamine use without a significant reduction in amphetamine-positive urine results. The disagreement shows why a treatment claim must identify its endpoint rather than treating all measures of use as equivalent. A safety pilot with limited enrollment McGaugh and colleagues enrolled eight people in an open-label study; seven completed…
A small 2026 study found structural brain differences and poorer performance on selected planning measures in early methamphetamine abstinence. Other measures were nonsignificant, and inconsistencies within the report require restraint when quoting detailed numbers. What the study compared Bristow and colleagues studied 13 participants with methamphetamine use disorder in early abstinence and 14 controls. Participants…
Background craving during abstinence and craving provoked by drug cues should not be treated as interchangeable. A picture-based attention study found associations with both, but their relationships changed when the researchers modeled them together. How attention and craving were measured Huang and colleagues recruited 134 individuals with methamphetamine use disorder. Participants performed a picture-based addiction…
More binding of a brain-imaging tracer is not automatically evidence of more healthy neurons. A methamphetamine PET study unexpectedly found higher VMAT2-related tracer binding during early abstinence, challenging a simple interpretation of this marker. The prediction and the observation Boileau and colleagues studied 16 recently withdrawn methamphetamine users and 14 matched healthy controls. Abstinence averaged…
A rhesus-monkey experiment linked methamphetamine-disrupted sleep with poorer next-day cognitive performance. It provides controlled animal evidence relevant to sleep as a contributing factor, without establishing that sleep disruption alone caused every deficit. Evening exposure and next-day testing Borgatti and colleagues studied five adult rhesus monkeys, four male and one female. Methamphetamine doses of 0.3 and…
A study found differences in learning from unexpected monetary rewards among people with methamphetamine-use histories, with an important sex-related pattern. Substantial age differences between the clinical and comparison groups limit a straightforward causal interpretation. Prediction, feedback and later recognition The study recruited 82 people from a compulsory drug-rehabilitation setting and 86 nonusers from a medical…
Withdrawal outcomes need not move together. A controlled d-amphetamine withdrawal pilot in people who used methamphetamine found a relative increase in craving after medication discontinuation, while Stroop cognitive scores showed no significant effects. What was withdrawn Thompson and colleagues enrolled 34 treatment-seeking adults in a four-week residential trial. Everyone initially received d-amphetamine, increasing to 30…
Lower baseline cognitive scores did not translate into significantly worse treatment retention for the methamphetamine group in a German inpatient study. The study is useful because it separates differences on entry from outcomes during treatment. A comparison within one treatment setting Behle and colleagues recruited 110 patients: 55 with methamphetamine dependence and 55 dependent on…
A large number of sequenced nuclei does not make an animal experiment a large human study. A 2026 investigation analyzed 36,376 hippocampal nuclei after methamphetamine exposure in mice, providing detailed cellular information from a much smaller number of animals. Controlled exposure and cognitive testing An and colleagues administered methamphetamine to mice by intraperitoneal injection, using…
A rat experiment reported that morin reduced several adverse effects after methamphetamine exposure. The results support further preclinical research; they do not establish that morin treats methamphetamine-related problems in humans. An animal intervention with several outcomes Anyanwu and colleagues assigned adult rats to seven groups, including controls, morin alone, methamphetamine alone, a methamphetamine-plus-fluoxetine comparison and…
Brain-metabolite differences and higher impulsivity can occur in the same methamphetamine study without forming a simple one-to-one relationship. A 2026 spectroscopy study illustrates why an imaging signal should not automatically be treated as a direct measure of behavior. What spectroscopy measured Dumitrescu and colleagues compared 20 recently abstinent individuals with 21 age-matched controls. Magnetic resonance…
A study comparing active methamphetamine use, remission and healthy controls found a more complicated pattern than uniform cognitive impairment. Its results do not show that continuing methamphetamine use protects cognition or that stopping causes cognitive decline. Three groups, not a before-and-after experiment Huckans and colleagues administered the Neuropsychological Assessment Battery to adults with active use,…
Inhibitory difficulty can appear in spontaneous behavior as well as on a computer test. A small human study found that abstinent methamphetamine-dependent participants interacted more with unfamiliar objects than comparison participants in a specially arranged room. A human version of an open-field task Henry and colleagues studied 16 abstinent methamphetamine-dependent adults and 18 matched comparison…
Lower visual recall scores do not necessarily indicate that stored memories are disappearing more quickly. A methamphetamine-dependence study found poorer free recall alongside preserved retention and recognition, a pattern that changes how the deficit should be described. Separating memory processes Morgan and colleagues compared 114 methamphetamine-dependent participants with 110 demographically matched comparison participants using the…
A controlled study found that a single dose of modafinil improved sustained attention across participants, while most other cognitive comparisons were nonsignificant. It supports a limited, task-specific effect rather than a general restoration of cognition in methamphetamine dependence. A placebo-controlled crossover experiment The study included 24 methamphetamine-dependent participants and 17 healthy participants. In a randomized,…
A small stimulation experiment in people with methamphetamine use disorder reported better visual working-memory capacity without a corresponding change in precision. Remembering more items and remembering each item more exactly are different outcomes. What the experiment measured Sun and colleagues compared intermittent theta-burst stimulation over the left dorsolateral prefrontal cortex with stimulation over the vertex…
A person may recognize what they intended to do yet fail to carry it out at the right moment. A study of methamphetamine dependence found this distinction in prospective memory: the ability to remember and execute a future intention. Testing future actions Iudicello and colleagues compared 39 methamphetamine-dependent individuals with 26 demographically similar comparison participants…
People with longer methamphetamine abstinence performed better on an impulse-inhibition task than those with shorter abstinence in a 2021 study. The comparison supports an association with abstinence duration; it does not establish that every individual’s inhibition recovers on the same timetable. The researchers compared different groups Liu and colleagues recruited 63 methamphetamine-dependent participants: 31 abstinent…
Drug-related images can change how a person selects a response even when average response speed does not distinguish the groups. A 2026 methamphetamine study found a cue-specific pattern of interference, rather than a simple across-the-board slowing. A task that separates location from the correct response Xu and colleagues used a modified Simon task in people…
Can Childhood School Records Clarify Cognitive Differences in Methamphetamine Users? Childhood academic records can help distinguish preexisting differences from later cognitive difficulties, but they cannot fully reconstruct a person’s original ability. A methamphetamine study used those records to improve a comparison that current education alone could not resolve. A historical anchor before use Dean and…
When Avoiding an Immediate Loss Can Undermine a Better Long-Term Plan A planning experiment associated methamphetamine use disorder with difficulty choosing a beneficial sequence when it required accepting an immediate loss. The proposed mechanism, aversive pruning, is narrower than general impulsivity or a preference for immediate rewards. A plan required looking beyond the next step…
Similar Balloon Choices Can Conceal Different Brain Responses in Methamphetamine Research A methamphetamine-dependence imaging study found differences in brain responses as risk increased, even though average balloon pumping did not significantly differ between groups. The task’s behavioral measure and its neural correlates answered different questions. What counted as risk in the experiment Kohno and colleagues…
Why Conflict Conditions Matter in Methamphetamine Cognitive-Control Imaging A small early-abstinence study found reduced activation in selected control-related regions during conflicting Stroop trials. The condition-specific result is more informative than a broad claim that the entire brain was underactive. The controlled task was not controlled drug exposure Nestor and colleagues compared 10 methamphetamine-dependent participants abstinent…
Working-Memory Load Reveals More Than a Single Methamphetamine-Related Test Score A working-memory imaging study found that people with problematic methamphetamine-use experience responded differently as task demands increased. Examining the response to increasing load can reveal information that a single score or one brain image does not. Several measures defined the ability Roy and colleagues compared…
More Brain Glucose Metabolism During Abstinence Does Not Necessarily Mean Better Performance Brain glucose metabolism increased during early methamphetamine abstinence in a small PET study, but that increase was not a direct measure of cognitive recovery. The study illustrates why biological change and improved function must be evaluated separately. Repeated scans in the same people…
Long-Term Methamphetamine Abstinence and Cognition: What Changed Over One Year? A longitudinal study associated sustained methamphetamine abstinence with partial cognitive and emotional improvement over approximately one year. It did not demonstrate complete recovery in every domain or prove that abstinence alone caused all observed changes. A longer interval than early-abstinence studies Iudicello and colleagues followed…
Can Reported Methamphetamine Use History Predict Who Has Cognitive Impairment? In one abstinent cohort, commonly reported methamphetamine-use characteristics did not distinguish cognitively impaired from unimpaired participants. Use history supplied context, but it was not an adequate substitute for direct neuropsychological assessment. The comparison reduced some major confounders Cherner and colleagues evaluated 54 methamphetamine-dependent participants and…
Exercise After Methamphetamine Dependence: Improvement Is Not Proof One Program Is Best An exercise trial reported cognitive improvements in men with methamphetamine dependence, but selected improvements within a group do not prove that its program outperformed every alternative. The direct comparisons and the measured endpoint determine the strength of that claim. Four intervention groups Zhang…
Lower Prefrontal fNIRS Activation Can Occur Without Worse Stroop Scores A 2026 study found lower activation in selected left prefrontal channels among abstinent participants with severe methamphetamine use disorder, despite no significant differences in conventional Stroop performance. Brain-signal differences and behavioral deficits were separate findings. What the investigators measured Luo and colleagues compared 73 abstinent…