Biomedical subjects

H V Curran

Publications and source records attributed to H V Curran.

44 records · Page 3Linked to original sources

PubMed1991

Benzodiazepines, memory and mood: a review.

The amnestic effects of benzodiazepines (BZs) have attracted considerable research interest. This reflects not only the clinical implications of memory failure for people prescribed these drugs but also the potential of BZs as tools in modelling organic memory problems. As well as impairing certain aspects of human memory functions, BZs affect mood states by reducing anxiety and inducing sedation. An unresolved issue is the extent to which the amnestic effects of BZs are separable from their sedative and anxiolytic effects. The present review focuses on this issue, first presenting a conceptual framework for evaluating the interrelationship between the various effects of BZs, and then summarising recent volunteer and patient research relevant to dissociating amnestic from other effects. Clinical implications are discussed in terms of the use of BZs alone or as adjuncts to psychotherapy for anxiety disorders, and attention is drawn to the need for more ecological validity in psychopharmacological research. Theoretical implications are explored in terms of BZs as tools in studying both memory failure and the relationship between mood and cognition.

Affect↗

PubMed1988

Antidepressants and human memory: an investigation of four drugs with different sedative and anticholinergic profiles.

The effects on memory and psychomotor functions of four antidepressants which differ in sedative and anticholinergic properties were assessed. Amitriptyline (37.5, 70 mg), trazodone (100, 200 mg) viloxazine (100, 200 mg), protriptyline (10, 20 mg) or placebo were administered in a double blind, independent groups design in which 90 subjects participated. Subjects completed a battery of tests before and 2 and 4 h after drug administration. The different antidepressants produced different patterns of effects across tasks. The relatively non-sedating compounds viloxazine and protriptyline produced very similar profiles and did not impair psychomotor or memory functions. In contrast, the two more sedative antidepressants produced global impairments on test of attention, manual motor speed, recording skills and primary memory. Although both amitriptyline and trazodone impaired performance on episodic memory tasks, the effect of amitriptyline was significantly greater and this may reflect specific anticholinergic action over and above global sedative effects.

Adult↗

PubMed1988

The effects on memory of pipequaline, alone or in combination with diazepam.

Pipequaline (PK 8165) is a putative mixed agonist/antagonist at benzodiazepine receptors. The effects of pipequaline and diazepam on memory were assessed in 12 normal volunteers. Diazepam 10 mg or placebo was added to two doses of pipequaline, 50 and 150 mg, or to placebo in a double-blind crossover design. Diazepam produced impairments of episodic memory. In contrast, the effects of pipequaline were minor. Addition diazepam to pipequaline increased drowsiness and general lethargy, with a less marked effect occurring for the higher dose of pipequaline alone. Pipequaline did not antagonise any of the effects of diazepam.

Adult↗

PubMed1988

A comparative study of the interactions of alcohol with amitriptyline, fluoxetine and placebo in normal subjects.

1. Twelve normal volunteer subjects were given amitriptyline, fluoxetine and placebo in clinically relevant doses, each for a period of 7 days. A minimum of 28 days intervened between each drug treatment. 2. A battery of physiological, psychomotor and subjective tests was administered before drugs and on days 4 and 8. 3. On day 8 a measured dose of alcohol was given and the tests repeated 1 hour and 3 hours later. 4. Before alcohol, little effect was shown on physiological or psychomotor activity. Subjective ratings indicated that amitriptyline was less-well tolerated than fluoxetine. 5. Significant differences were found for many measures after alcohol but there were few differences with respect to the drugs.

Alcohol Drinking↗

PubMed1987

Differential amnesic properties of benzodiazepines: a dose-response comparison of two drugs with similar elimination half-lives.

The effects on memory and psychomotor functions of oxazepam (15, 30 mg) were compared with those of its chlorinated derivative lorazepam (1, 2 mg) and placebo. Forty five volunteers took part in a double-blind, independent groups design. Subjects completed a battery of tests before and 1.5 and 3 h after drug administration. Lorazepam and oxazepam had similar dose-related effects on tests of attention, manual motor speed and recoding skills and all active treatments produced similar levels of subjective sedation. Both drugs caused anterograde impairments of long-term verbal memory and had no effects on short-term verbal span or recency. Neither drug produced retrograde amnesia for material learned before drug administration nor affected retrieval from semantic memory. The high (2 mg) dose of lorazepam positively facilitated recall of pre-drug information. The magnitude of anterograde amnesia produced by the two benzodiazepines was not linearly dose-related in that the two low doses had similar effects whereas the high dose of lorazepam produced impairments many times greater than oxazepam 30 mg. We conclude that drugs with similar half-lives may have similar effects on some cognitive and mood factors but be completely different in terms of amnesic effects. Differing potencies of the two drugs may be a more important factor determining amnesic side-effects.

Adult↗

PubMed1986

Effects of repeated doses of fluvoxamine, mianserin and placebo on memory and measures of sedation.

The effects on memory and learning of fluvoxamine 50 mg twice a day were compared with those of mianserin 20 mg twice a day and placebo, each given for 8 days in a double-blind cross-over design to nine healthy human volunteers. At least 1 week was left between the 8-day courses of drugs. Subjects were given a learning task (three trial recall of categorisable word lists) before and 3.5 h after a morning dose on day 1 and before their morning dose on day 8. Delayed recall was assessed on days 1, 4 and 8. Fluvoxamine had no effect on memory performance. Mianserin reduced learning and recall after a single dose but had no effect on day 8 of treatment. The single dose of mianserin had no retrograde effect on memory, affected primacy and middle position items but not recency in the serial position curve, and was seen in reduced inter-trial subjective organisation of recall. Subjects' performance on the first trial of the memory task correlated significantly with their performance on a simple reaction time task, with finger tapping speeds and with their subjective ratings of alertness. It was concluded that the impairments of memory produced by one dose of mianserin are partially by-products of the sedative effects of the drug. Tolerance to both memory impairments and sedative effects built up over the 8-day treatment of mianserin.

Adult↗

PubMed1986

The psychopharmacological effects of repeated doses of fluvoxamine, mianserin and placebo in healthy human subjects.

The psychopharmacological effects of fluvoxamine, 50 mg twice a day, were compared with those of mianserin, 20 mg twice a day, and placebo, each given for 8 days in a double-blind crossover design to 9 healthy human volunteers. At least one week was left between the 8-day courses of drugs. Testing was carried out before and 3 h after taking the morning dose on Days 1 (pre-drug), 4, and 8, and comprised EEG, cognitive and psychomotor tasks, and self-ratings of mood and bodily symptoms. Fluvoxamine had no effect on any of the EEG wavebands, but mianserin increased voltages in the slow wavebands as compared with placebo. This effect was particularly pronounced on Days 4 and 8. Mianserin significantly decreased critical flicker fusion frequency and speed of reaction time, and slowed down tapping rate; digit symbol substitution and symbol copying test performances were also impaired by mianserin. These effects were most marked after the first dose and had lessened somewhat later in the week. Symbol copying was the only task impaired by fluvoxamine as compared with placebo. Mianserin caused drowsiness after the first dose but this effect declined by Day 8. By contrast, fluvoxamine induced feelings of anxiety, sweatiness, trembling, nausea, loss of appetite, restlessness, muscle tension, irritability, tiredness, headache, and dizziness; these effects were most evident in the middle of the week and relatively reduced at the end of the week. Mianserin produced a few of these effects but they tended to be maximal on Day 1 or 4 and then to wear off.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1986

Tranquillising memories: a review of the effects of benzodiazepines on human memory.

Studies from 1973 to 1985 of the effects of benzodiazepines on memory are summarised and reviewed. Anterograde amnesia appears a common effect of all benzodiazepines although its onset and duration vary with the particular benzodiazepine, its dose and route of administration. Memory impairments increase with task difficulty. There is some evidence that partial tolerance to amnesic effects develops with repeated doses of diazepam, but research with other benzodiazepines is inconclusive. Amnesia is in part a by-product of the sedative action of benzodiazepines, although these drugs may also have a specific effect of disrupting the consolidation of information in long-term memory. State-dependent effects are partial and relatively small. Methodological problems are discussed and attention is drawn to the lack of repeated dose studies, of studies with patient populations and with anxious volunteers.

Amnesia↗